I have had similar problem with finding a quality replacement switch and not paying an arm and leg for one. Price one from Ingerssol Rand, for example, and they are over $80 if I recall. Similar Square D switch from local well-stocked hardware store was closer to $30. Took me a while to find out they carried them, as they were not shelved, you had to ask at their electrical supply desk.
I just got myself into the habit of unplugging the compressor at the outlet.
have had two issues that did not help the switch out due to being plugged in. One I am pretty sure was a lightning hit that did fry an IR switch, the other was an air line that popped off so the machine ran (for hours??) until the thermal switch on the motor turned it off and I think all the heat did the switch ill will.
At any rate, since I unplug it when I leave the shop I have had no pressure switch issues.
