On the opposite side of the cylinder head from the vacuum control, there is a port. It looks like it has threaded fittings already attached? You can use that side (compressor side) to shoot paint through an airbrush.
Also, from what I can tell, that’s a basic diaphram pump… probably doesn’t need oil. If you decide to get fancy and hook up a vacuum switch, you should check Joewoodworker site for his info on MAC valves.
For anybody looking to score a good pump for a good price, follow this link. If I didnt already have a working pump/had more money id be all over it, I hope someone buys it to make boards…