Hmmm, it wouldn't be realistic to jam an '040 into a regular A1200 case would it, so how does £20 inc P&P for the A1200 Ram card catch you? If you recon an '040 could work in a trapdoor then I'd part with £50 for a 25MHz one, a bit more for faster ;-)
... time to heft my 1084s down to the TV repair shop I guess ...