Currently 1 of 2, I bought and own one of these beauties!

I will redo this suggestion if the other one is sold after it becomes tradable.

Sale #1:

Sold for $300 on the SCM:

https://imgur.com/kAWb3Fk

Keys sold @ $2.30 that day:

https://imgur.com/2t8dXJl

$300 / 2.30 = 130 keys

Like I said, if the other one sells in a timely manner then I'll update this.

I plan on keeping mine though, so this may or may not be the only sale.