LnS,
How about a DH60
? Admittedly it may only meet No 1 during summer, and I'm not too sure about No 7. The downside is I doubt you'd find a decent one for £15,000
At the opposite end of the scale how about one of Ghengis's favorites:
the Easy Raider, or the Escapade . They aren't areobatic, but just about squeezes into the cost requirement, but you will have to build it!
Brooklands