Yep, sounds about right W.B. Phonogram, Inc. was renamed to PolyGram Records, Inc. in July 1981, and absorbed the operations of Polydor Incorporated and Casablanca Records at the same time, so no later than 1981 for this (unless there was surplus label stock to be used up - accountants don't like waste!).
Actually, based on the address shown on {Images #484889 & 484890} (810 7th Avenue, New York, NY 10019), this would have been around 1980-81 - the 53 code signified a pressing by Keel Mfg. of Hauppauge, NY, which around 1981 was rebranded as Hauppauge Record Manufacturing Ltd. At this point, they still had the 2.75" diameter pressing ring, but that would change within about a year or two.
Original cat# but most likely a mid to late 70's re-issue judging by the label. The covers steal the show here with Tobacco Road a stand out but Deep Purple did lift the riff for Black Night off the opener (We Ain't Got) Nothin' Yet.