whats it worth

I would first match parameters and price ranges per specific parameters of your pre to compare with to derive the right price.

Are you asking about a Bryston 1B preamp? Lot of info using Google.

Wow, BRB, that brings back some memories. My first store
was a BRB dealer for the short time that BRB was a company.

BRB submitted an amp to TAS and got a glowing review. This
amp was in the same genre and price range of the Hafler
DH200/DH220, B&K ST-140, Amber Series 70 of the time.

BRB, more or less, sent TAS a "prototype"
amplifier. Once the amp came to market, there were numerous
changes to it and sounded completely different from the
review sample.

Well, needless to say, BRB tanked almost as fast as they
became a company. They did have a pre-preamp also, which is
the one you have.

IMHO, the preamp you have is probably only worth around 25%
of the retail price, (if that).

Sorry, you happen to have a piece of gear that has a storied
history, (and not a good story).

thanks Mofimadness, appreciate your input.