What is the blanket with the number called on a racehorse? Best Answer Will be Chosen!?

I am doing a costume contest with my horse and I want to be a racehorse and a jockey, but I don't know what the blankets with the numbers are called. I need to find a website where they sell those so any websites would be helpful also. Another thing, What is the head piece that they put on the horse so that they can't see the other horses? I will choose a best answer so answer wisely! Thank u in advance!