you can also buy a 1.6 block along with an adapter kit from one of the vendors. Just slap the 1.3 head on the block and install it. Later, you can add a my-side carb (or switch to 1.6 FI - save the harness intake, ecm and fuel tank!), thorley header, etc, as money is available.
Or you can just do a complete 1.6 transplant.