Welcome to ECN forums, from one of the Jersey Guys!!
IMHO, the customer should lean in the direction of the mfg of their genset. Kohler, Cat, etc.
Are you looking for the prime mover, or the gen, or both?
Have you tried a local Vo-Tech? Or possibly a County College? Another would be a private 'Tech School', like Lincoln Tech here in NJ. Must be some up your way.