Unless its wounded i would just run the short block as is. Spend your money on the heads and any other odds and ends you need, like ignition, carb, etc. save your coins and next teardown you will have all the goods to hang on a well done short block. Otherwise you'll just end up with crap shoot used, mismatched, machine work not ideal for later, or stuff you wont want when you do it right at some point.
There is no way that you will be able to get into and back out of the short block, and do heads for your budget. The power is in the heads. Buy the smallest combustion chamber aluminum head (75 cc?) and a nice hydraulic cam and timing set. If there is money left over, put that into the heads too.
Do you need any of this stuff, and is this in your $2,000 budget?
Oil, oil filter, air filter, fuel filter, fuel line, fuel clamps, anti freeze, radiator hoses, clamps, belts, fasteners, gaskets (timing, water pump, head, exhaust, intake, carb, valve cover…), gasket sealants, cleaners, paint, spark plugs, plug wires, oil pump, oil pump drive shaft.,,,,,,
