IMHO, the seller made out great on that sale.
I've seen mint M160's sell in the mid 200's or less.
(yes I had my eye on that exact one on e-bay too!)
Sometimes Stephen Sank has "DX'd" Beyer ribbons on his
website BTW. You can pull it up via a search engine.
(sorry I don't remember it off-hand)
This is where he surgically implants a RCA 77DX ribbon to
enhance performance, for not much more than this M160
sold for on e-bay.
Chris
P.S. Been enjoying my newly acquired Electro-Voice EV 666.
(scored for $100! They sometimes sell $400+ when mint)
It's reputed to sound just like a RCA 77DX ribbon run
through a quality tube mic pre, per Bob Ohlsson no less.
Only caveat is that they're now non-repairable due to
lack of parts if they break down.