Grainger, MCSDirect, ENCO, Rutland. Any of the tool mongers on the net.
Yes you definitely need a good capacity quality air desiccant drier, not just a filter.You do not have your location in your info (good idea to put it in there for help reasons) so I have idea how humid you are.
I use one even here in the desert. Air drops out water when you compress and expand it.
Moisture cares not if air is compressed with either a piston or a diaphragm compressor.
banger