A 1/6 share in an RV7 will run to between £6k & £10k depending on engine hours, group funds, avionics fit, etc
You would be EXTREMELY lucky to find a 1/6th share in a "7" for even the top price! Maybe a "6", but good examples of these are going for over £60K now! I would agree though that an RV is the sort of aircraft the OP should be looking at, also monthlies you quote would probably be a bit lower than that for a 6 person group.