I have a 1986 Isuzu trooper 2 4x4 the engine needs to be rebuilt, but I want to know are there any aftermarket?

I need to know if there are any aftermarket performance parts for this vehicle such as over sized pistons or a stage 1 camshaft, performance carburetors degreed timing gear ' header or cat back exhaust system. She needs more power or is there another engine that is a fairly simple swap??