Try shopping at the Good Will or Salvation Army for a pair of attractive inexpensive drapes. You might find a pair to fit the window, and if not you could narrow them and cut them down to fit. They wouldn't be hard stitching them on a sewing machine.
2 ideas come to mind. Find 2 of the same design you like in dishtowels sew them together to get your lenght then make a seam for the top depending on your width needed for the type rod you would choose.
My favorite though, which I use in almost all my windows in some way, whether it be large or small version, is to decorate the glass with gallery glass. It's a craft type liquid you find in walmart or any craft store.
The choice of colors to pick from are numerous. You first need to get the liquid leading there in that section. You take the liquid leading that comes in the pour top bottle and just draw out your design (like coloring). Then you let that dry for about 48 hours.
Then you fill in the spaces with your color choices of the gallery glass. They too are in bottles with tips for pouring and filling. To make fine tiny lines put a piece of clear tape around your nozzle tip so it's more fine and not a fat line.
When you fill the inside spaces with the colors use a tooth pick to spread it around and pop out any bubbles you see. You can use saran wrap balled up in your hand to pat at the paint colors to give different texture looks.
When all of your scenery dries, it looks so pretty and has a stained glass look. It peels right off it you ever tire of the look and can be put right onto your windows again by simply spraying them lightly first with windex.
For non-removable windows or glass simply take a big piece of cardboard and tape a big piece of clear saran wrap over it being sure to tape the back side so it stays on and is pulled it tight. Then lay your design under these two layers and trace over the design with your lead liquid, let it dry for 48 hours. Then fill with your colors. When its all dry, peel off and spray your window with windex. Then add the design to it. I always take my windows out and do this procedure with windows lying flat with my design under the glass and taped to the other side.
This beautiful look adds privacy and give off such pretty colors from the sun shining through.
You can find some gallery glass paints and leading on Amazon:
Here are pictures of two of my windows in my home. One is partially covered the other one I use the gallery paint that is a frost type white, but when it dries it is just clear. The crinkling look you see around the rose is the frost color and I used saran wrap balled up and moved it around on the glass in a patting motion to give it a textured look.
I mixed green in which gave it a green tint. That picture was taken from the inside view. The other garden scene is on my laundry room window. I have double storm windows so I did it on the outside window. that picture view taken was from outside. When the lights are on inside & its dark outside it looks so pretty and gives privacy from anyone seeing half way up the glass. On it a free handed a birthbath with water and a bird below are all sorts of flowers and rocks with turtles on them. when you put your design on with the liquid lead bottle, try thinking in layers. put the things farest you want to seem small on first then put the larger things on last. it makes it seem more 3-d and realistic.
I do my scenes free hand but you can print coloring book type pictures from your printer on free clip art sites or use coloring book pages. You can even trace over pictures in magazines.
The paints are a bit expensive but eBay sellers often sell them cheaper. Store and use them upside down (all your paints) so the ends do not harden. Have fun with it, if you mess up, just wipe off and start again.
heres the garden scene using the gallery glass, my picture is taken from outside so my screen is over top of it.
You can buy paint-on window frosting from hardware stores and even use a stencil to make it more interesting.
A really cheap fabric covering would be to take a pretty pillowcase and open it along the longer side seams, that should make it long enough to cover the drop.
I did a custom order mini-blind. Got it when Montgomery Wards was having a sale years ago. Turned out to be very reasonable and looks nice from the exterior of the house.
If you have a Home Depot in your area, they have self adhesive (static cling) type stained glass in many designs. You get it wet and smooth it on the window. It sticks till you pull it off. They are easy to cut and look very nice. They may be available at other hardware or home decor stores.
A pretty table runner would be just about the measurements you indicated.
Use contact paper. I did a window years ago with a stained glass pattern and it is still looking good.