I can lend you a pair of shoes on the understanding that you clean all the mud off afterwards and that you replace them with a pair of the same quality in the unlikely event that you damage them.
They have cleats, so you might want to use clipless pedals. Again I can lend you a pair. Same terms.
However, if you haven't used them before, a race may not be the best place to try them out for the first time.
Up to you.