Since the motor is out I would change all the gaskets (you can get a gasket set for cheap, don't do the HG). Definitely do the timing belt, water pump, and thermostat. As for timing belt replacement, you only need to make sure the crank dowel key is at 12 o'clock, and the cam gear mark is lined up with the mark on the head. The oil pump gear doesn't matter, it doesn't effect the timing.
As for the A/C, depends how the A/C acted before. I installed A/C into my Ranger that didn't have it from factory, and I stayed under $250 for a whole system, including a charge. In your case, it could be something simple such as a clogged orifice tube (common Ford issue).