I don't think you'd ever get those airframes onto the civvy register.
Surely an ideal use for the COMR concept? Previously only used with Civilian Type Certified aircraft (B212/412, AW139, SA365 etc), but I'm sure the MAA would have a mechanism to use military types on a COMR contract (some rules here:
http://www.maa.mod.uk/linkedfiles/re...ies/ra1123.pdf)