Yes, it's kind of like the lonely Maytag repairman.
I just bought a new fuel shutoff at a neighborhood lawnmower shop. The
original brass shutoff failed several years ago, and I replaced it with a
newer, cheaper plastic Seagull shutoff valve, which started leaking
recently. The lawnmower fuel tap is brass and fits perfectly.
There is a Seagull shop in San Francisco. The best source of parts appears
to be Sailorman in Florida, although I've never had to order from them.
They have the Seagull parts catalogs on line. I don't have the Sailorman
URL handy, but it can be found in the links on the Potter Yachters web page
<http://songbird.com/py>. I've heard of another Seagull shop in Washington.
Harry