Just lucky you found it as you are right as never see it before. As for the price that would be up to people buying it. I have see some padlock gone up to $3000.00 or more has no key for it. It really surprise me as sometime thing just pop up and wonder where it come from all these year as we don't know about. I has been locksmith for about 25 years have see a lot of padlock and safe. This is why I love about "The Anique-Lock.com" as learning about all these lock from other people that they have for whatever they doing with it. Good lucky on your lock hoping to see some more old lock to look at...
Timothy....