Need a replacement check valve for an airbrush compressor

[larryq]

I have an airbrush compressor that does up to 100 psi. It's 20 years old and the check valve probably needs to be replaced--I'm doing a general overhaul, pressure switch, etc.

I'm not too familiar with check valves and wondered if someone could point me in the right direction for the replacement?

Specs: the top and bottom openings are 1/2" diameter, the threads on both ends are 3/8" / 24 pitch and the side vent, the blow-off, is M5 / 80 pitch. I'll attach a couple of pics showing the dimensions too. Thanks for the help.