I have some good information from Jes at Hawke Sport Optics.
The scopes they rate for airguns:
Vantage - Light gas piston and spring rifles Only 12 ft lbs and under.
Airmax 1" and 30mm - Rated for all spring and gas piston rifles.
Panorama - Rated for all
Endurance - Rated for all
Sidewinders - Rated for all
Frontier - Rated for all
I have four Hawke Airmax 4x12-40 AMX on four of my FWB 300's and one 2x7-32 AMX on another. Even though I like the 2x7, I'm going to swap it out for another 4x12. Fits my needs and doesn't break the bank.