don't know about mercury but a few months ago I got more relays than I could ever handle could not even move them myself I found a buyer for all them and dint mind any loses as I would never have been able to tear them all down but I bid $100 and won a lot as in alot lol 5,000,000 of these old 60's era pkm1 relays from Russia with silver contacts almost 11 pallet boxes filled to there brim with these. none really in good shape like they were bad made or ripped out of things, I dint get a story but that they were stored in a warehouse and forgot about.
they were worth $15,000 to me from my buyer which was just fine even if they were worth $10each I dint care cause I had to move them fast with no space to save them or for that matter move them without dumping loads into my truck as I had 24hrs to take them or forfeit but could not find more info on them and their worth but a few ebay items that never sold