Kim,
it ain't as easy as you might think . You can contact John Ashbey (Ashbey Photography) who is one of the top show photographers in the country and I believe he gets them made up for other show photographers. I actually had mine custom-fabricated.

On the other hand, with a bit of creative skill, you can make them up in PhotoShop complete with the club's logo and simply drop them into the finished images. Just keep track in a notebook which photo you took and in what order. If you prefer, use a wipe-off sign & marker to indicate the win and drop in the finished sign over it in post-production.

Good luck.

Jim