Except the "SKS-D" marked canadian imports brought in marked as such by China. They did adopt the term eventually at some point.
That is an interesting point, but that particular rifle is a strange bird in itself. The ones that I've seen, and that Joe has in his database, are rifles that were made in the 2000s, over a decade after the original SKS-30 was produced. Those guns are also not new production like the SKS-30, they are modified existing rifles that appear to have been produced by the same arsenal that produced the MC-5D. And of all the pics of them I have, only ONE rifle says SKS-D on it, and it's markings don't look anything like the other rifles nor does the construction of the rifle. With that said, given when they were produced, I can only guess that the name may have been used after years of it being incorrectly referenced.
There are 3 types common up here. Of the one type labelled sks-d... all of that type bare the same markings.
RUSSIA SKS45: Tula 49, 50, 51 x2, 53 x2, 54, 57(И); Izhevsk 53, 54
POLAND SKS45: "W.P." Marked Tula 52
CHINA TYPE 56 CARBINE: /26\ 60 "S", 61, 64, 65, 66, 79; /UK5?\ 69; /256\ 70; /316\ 70;  Stamped Receiver 70 x2; /306\ 71; /416\ 公安 73; /0412\ 78
CHINA Civilian: SKS-D (XZ), "SKS-D", Cdn Para x2
N. KOREA: T63
YUGO PAP M59: 66 C-Series x2; PAP M59/66a1: 73 J, 83 T
ALBANIA 561: 78
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