You know a lot of those SLR cameras have a single lithium battery, right? Did you simply try changing the batteries first? Meanwhile, you can sell the cameras as-is for parts or repair on eBay.

I have my old Canon AE here, and I had a Contaflex (Zeiss Icon) that I sold on eBay years ago. And some really old collectible bellows Kodaks.

Bandage comes off this afternoon and I suspect I will need an antibiotic for a few days after that. There is a routine of elevating the leg and icing that will continue for a while also. Not quite ready for prime time yet. :-)