How much does a cryptorchid surgery cost?

we found a stray 14 months ago. He was about 5 months old. Part Bassett part Coon dog. We thought he was fixed because he didn't have testiles. We took him to vet to have him scanned for a chip. He didn't have a chip. Well today the area around his privates is swollen and he is limping. I am afraid he has not been fixed and he is in trouble.