One thing you could do to get uniforms, jackets and such is to put a post up on Freecycle or a Yahoo group. We have one here in Jefferson Parish, which is like a county. Maybe you can check to see if you have one in your town or area. You can just post on there asking for what your looking for and hope that somebody has it.
You never know, someone's child could have outgrown theirs and it could be in great shape. I know I have some right here that I am about to list in hopes that someone can use them. I am sure since you're on this site that you are like me and hate to have something not being used when you know someone could be using it. Make sure you post what you have lying around not being used. That way it keeps things fair. Also remember it's Freecycle which means Free