If no Auster appears, you might consider an N-registered C of A type that is already in the UK, assuming you wouldn't want an importation project. This would potentially open up choice of aircraft types. Maintenance on N-register is very unlike that on EASA registers and can be simple, I believe even in the UK if you make good contacts.
Types that come to mind on that basis, other than the Family Cruiser, Pacer and Stinsons already mentioned, and subject to availability (as the saying goes)...
Cessna 170 (the practical choice)
Luscombe 11A Silvaire Sedan
Taylorcraft Model 15 Sedan
Aeronca 15AC Sedan
Fairchild 24 (now we're getting a bit exotic
)
Etc.
Best of luck