Congrats on getting the relay out. Note on the bottom of the relay that the coil is across pins 3 and 14. In this day and age, that's an oddball arrangement and probably why the new-old-stock relays are selling for a mint. Nobody's making them like that now. That pin arrangement used to be kind of the norm.
My worry is, is that you'll find some NOS relays, pay a lot for them and their contacts would have been in storage for all of those years just oxidizing away. Those relays were troublesome, even when the products that used them were current. I've seen those relays in B&O and several other brands. They were so troublesome when the products were current, that some manufacturers started substituting the yellow Aromat, gas-filled relays. The gas-filled (at least we thought they were gas-filled) relays were sealed. You couldn't clean them, but then again there wasn't a need. They stayed reliable.
Panasonic acquired Aromat and they have the sealed relays today, but not with the same pinout. I think you'll have better reliability if you get some modern, sealed, sub and pin map. It's really not hard. You know where the coil is. You just have to find where the com and N.O and N.C. contacts are. My guess is, the COM's are pins 8&9 and the N.C.'s are pins 2 & 15.
If you're going to spen a lot of money on the relays, you might consider putting in ZIF (Zero Insertion Force) sockets. They'll allow you to remove the relays at will and can make it easier to add pin mapped replacements at a later date.
