I hate to put a damper on this, but the obstacles to over come would be huge, having some experience of certifying odd aircraft. For a start you would need the backing of a design authority, this could only possibly be Westlands, or may be Bristow, but I am sure they are busy with other things.
You need this for the approval of Maintenance Schedules, flight test schedules, flight manuals, and the issuing of service bulletins.
I believe the authority for the Vulcan was Marshalls.
When the ex Royal Jordanian S76s were certified, we had to get certification from the high ups in the R.J.A.F. that they had only been flown in accordance with the flight manual, and that all parts fitted were from an approved source.
As for the aircraft themselves, things to consider would be, engine and gearbox overhaul lives, engine and gearbox finite component lives, rotor blade finite lives, and engine cycle lives.
You would also have to maintain a bonded store for any parts held, and approved certs for those parts.
I am sure I have only scratched the surface, and there are many more considerations.