I just bought an old 35' Bertram down in Fall River, MA that has a Garmin 215 with the GUS182SL, and I'm looking for the GUS181SL. The smaller chart's GUS200SS and GUS201SS also cover my home port of Salem, MA.
I had a "wanted to buy" thread over on another site for this chip, too bad google brought someone else in to hijack my thread when I finally got a reply....
Maybe I'll have better luck here?

Thanks,
Mike