Equifits are really popular, but can be pricey, especially the newer models. The original front boot model is around 130 at SmartPak, I think, which isn’t bad, and would probably be appropriate for you.
I use Eskadrons for schooling, they’re durable, you can just throw them in the washing machine, and you can get a set of front and backs for like $130. I do the hunters, so don’t boot for showing obviously.
Are you required to show in boots? You don’t have to have them if you don’t really need them. I would also check around your barn and see what the other riders use and ask your trainer if they have a preference. Show barns tend to have preferences for what “look” they want their horses to have at shows, and there may be brands/types of boots that they would rather not have you use. You don’t want to go out and buy a nice set of boots and then have your trainer not like them.