The A14 block is dimentionally interchangeable with the A15, & both the A15 crank & rods are used, but from memory the pin sizes are different, so some work is needed there.
I also think that there are different versions of the piston, so check them all for the best one for your needs

I also believe that some Mishy-bishy [Sigma] pistons can be used with a little work.

The block in the picture is either 78.5, or 79mm in bore size.

Just understand that this is not my block, & I have never built a big bore A15, but the info is gleaned from a friends engine, so do your homework & procede carefully.

If running boost, then I recomend that you maximise the gap between bores by using a smaller bore size.