Hi Larry, I also found another relay way less expensive than the P&B part: https://www.digikey.ca/en/products/detail/cit-relay-and-switch/J1031C24VDC-1 5S/14001944 And there is a lot in stock. The coil will still replace R531, but with a 5.1K in parallel to match the 2.2K value. 73, Jacques, VE2JFE in Montreal