It looks like Sowerby 2631, although I have reservations about the stippled panels. In my time (early '50s) we were making it without the stippling. The pattern number suggests origins in the early '30s, when the panels were, I think, sometimes acid etched. I would make a fairly wild guess and say that the stippling might have been done after I left as an alternative to acid etching which I doubt if Sowerbys ever returned to.
Adam D.