Yes, you need to get other quotes from other vets.
I paid about $260. for a gelding surgery done here at the farm last year, including shots.
Question: Are you sure your colt is really crypt.? I would ask another vet his opinion, maybe even three vets.
We had a colt that we waited and waited for his one testicle to drop, (some of them do go about three years), but we were patient with this colt because he was a well behaved boy. Finally at four years of age, we bit the bullet, made arrangements to have the surgery done, (were quoted about $600 at a clinic out of town), and much to our surprise and delight, as soon as they sedated the boy, that testicle dropped down and he was easily gelded for about hundred bucks. Yes, prices have gone up, but not that much.
Wendy