So, without counting the modified Stormtrooper helmet from the old comics, there's 5 different variations of Seatrooper helmets in the artwork posted in this thread. This said, because I'm not a sculptor, if I get around to making a normal Seatrooper costume at some point, I think I'll just try using an existing Scout Trooper helmet and then doing some mods to it to make it look somewhat more "Seatrooper-like". The hard thing would be deciding exactly "what" to change, since every one of those pictures up above is a basically different shaped helmet.
Forehead "sensor array".....sometimes there, sometimes not. Rounded Scout ears....sometimes there, sometimes not.......sometimes a bigger lense area then normal Scout helmets, sometimes not.......etc, etc, etc.