Hi Peter, the GPS has a serial to usb converter built into it so that it shows up on the pc as a com port, i didn't buy the gps for the purpose of using it with EQMOD but i just happened to try it and it worked.
the name of the seller is "dtwproducts" and if you search for "GlobalSat BU-353 USB GPS" you shouldn't have too much trouble finding it.
(i just looked and they have them now for $68.95 + postage
)
i have bought a lot (20+) of these types of gps units, usually i get a different brand but i couldn't find them so i got a few of these GlobalSat ones and they seem to be better quality (not to mention they have the better chipset).