There is a dedicated glow engine forum
Glow Engines - RCU Forums
They will soon tell you if you have a hidden gem. But I think the answer will be 20 -30 $ for the 2 st and a little more for the 4 st [ Orange fuz]
Your 72 meg gear will be fine, most clubs are still OK with it. New batteries would be good though if the old ones have been flat for a long time.
As others have said you should find someone to check them over for safety and then buddy box with you for a few flights. None of the models look extreme and look OK as a first nitro low winger. IMHO though the chance of a low airtime pilot with only foamy experience getting them off the ground and back down to a safe landing is almost zero.