Anything is possible if you are keen enough. A good friend had a 1760cc A15 built for racing. It featured custom made forged pistons, Carillo rods and a welded and offset ground crank. The
block needed relieving for the rods to clear in the bottom of the block. This was a "cheater" engine which was run in in a 1300 to 1600cc saloon car class. This motor was still a screamer
(9000rpm) and had stacks of torque. Sadly this engine has "disappeared" and many of the people associated with it still won't acknowledge it's existence. A good race engine builder could do
the calculations and build a similar short block, though it would'nt be cheap. Similar engines being built here in New Zealand can cost as much as 30,000NZ$ (15,000US$)but you could probably
use more standard parts with a little cross referencing in various component suppliers catalogues for the correct con rods and pistons. Get friendly with some engine machinists and pick their
brains.