If you want to keep your block, you can try to find a B17A crank and rod set. They are uncommon, but can be found if you are patient. The B17A and B16A use idenical engine blocks so the guts can be directly swapped as a crank/rod combo. Reuse the B16A pistons however, as they are higher compression then the stock B17A units.

Otherwise, start thinking of a B20B/Z block or some other import car in the 3.0l class (Supra, 300ZX, 3000GT/Stealth, etc)