I have the manual top parts now (top frame going back together) and I have a spare set of power top side rails. They will need some work due to abuse on a manual top car, though they are not rusted or broken or bent.

'67-68-69 Camaro and Firebird top frames appear to be the same. Power top frames have several components (all bolt to the side rails) that are different than a manual top. If you find a pair of good side rails with their attaching brackets and links you are good to go.