I have some 2B-LP Pro, as well as 3B, 4B, 7B Pro. As you say, they have variable gain. Also, they are awesome amps.
According to James Tanner of Bryston:
2B-Lp vs Original 2B
www.audiocircle.com
So looks like your eBay item was from a Canadian flight-simulator. I would hit the BuyItNow button if the price is right...