Well, for $500 you can get a start on buying the parts. A gasket set (Felpro) alone will set you back $200, a cam $150, pistons $160 (unless you want forged at close to $100 each) uh oh we're already over $500 and we haven't included machine shop work, ported and polished heads, valve train parts, moly piston rings, new oil pump, new water pump, 62 mm throttle body, ported and polished exhaust and intake manifolds, custom intake, new cam and crank bearings, and on and on. You also probably don't want your new motor to run through a dirty radiator so you have to get a new one or at least clean out the old one. Then incidentals like spark plugs, new plug wires, oil, antifreeze, belts, clamps and other things will set you back about $200. Start with buying the parts you know you will need until you decide on a final plan for your engine.