I found this supplyer:

AZ970E-1A-12D AMERICAN ZETTLER | Power Relays (20 Amps to 99.9 Amps) AZ970E 1A 12D | Onlinecomponents.com

$3.46 a pop. There is a minimum $20 charge in the US. Someone can buy 6 and share them among us. I'm going to need one soon. I noticed the odd time the air pump wont kick on

p.s. Great research Super Dave!