Upholstery screw ( could be LBC related)

Listers

I'm looking for a source of stainless pan head
upholstery screws. I guess pan head would be the term
as the screw I'm looking for is a pan head type sheet
metal screw with the "finishing" washer attached to
the screw. ( make sense?) 
Any suggestions/ (I've already tried a local marine
shop).

Larry Pitts
60 Bugeye
76 MGB (with new front bushings and tie rod ends-
interesting project-nice ride)