Peter and Bob,
I'm going to stick my neck out here and just say, "no, it won't work." The A7 stroke is 11.4mm less than the A10, so, unless you came up with pistons that had that much more height above the gudgeon pin, compression would be so low as to make running questionable or plain crappy (regardless of the piston diameter). Having said this, I look forward to our extraordinary, experienced experimenters to jump in and say, "Richard, you are wrong, yet again."
Richard L.