Cornfed Hick
Ancient Mariner
I checked my LP pressing of Powerslave, serial number SJ-12321, which, again, was purchased by me from a reputable record store either the same day or within a couple of days of the album dropping, back in 1984. My vinyl has the same etched-in numbering, though the last digit is a one, not a five, which I think only means that mine was an earlier pressing. (Side A is ST-1-12321-z1, Side B is ST-2-12321-z1.) There is no triangle whatsoever, which suggests that it may have been forgotten on the original stampers and etched in on later pressings. I believe the "ST" marking denotes the Sterling pressing plant -- does yours have the word "Sterling" stamped (not etched) into the deadwax? (Mine does.) Incidentally, mine also has the "THERES ONLY ONE um" marking on Side A, but the "THATS FUCK um" marking on Side B evidently was etched out, presumably as it might be offensive to US audiences. In short, nothing definitive, but I wouldn't worry too much about it being counterfeit simply because the triangle and pressing numbers are etched, rather than stamped, into the deadwax. The fact that your copy has the textured cover should give you more confidence as to its authenticity, too.