I had planned to wait until the chassis was complete before getting a donor car...but thought I would keep an eye on the local ads anyway just in case. Eventually spotted a little beauty only a few miles away so went along for a look and a test drive. A short while later it was back in my driveway!
I had to wash it when I got it home as it had been a bit neglected over the winter...now it looks great. It's a 1.8 Eunos and had failed its MOT on rotten sills but had no other issues. Engine & box seemed strong so I will hopefully just be able to chuck it straight in the roadster when I'm ready. Longer term plan after IVA will be to rebuild it and stick on a wee turbo.