Well, this tape sure is..
Another of the few companies in CAnada that made cassettes was General Recorded Tapes, or GRT..
More often than not, the label was on the *outside* of the box, in a 'clam shell' style case.
This didn't help with wear and tear , so *any* in as good shape as this 40 years later is a find.
Otherwise i'd have passed on this one maybe.. although it fits the bill regarding historical significance, as Deep Purple covered at *least* one of his songs.. and it looks to me, according to the tracklist , that they may have covered more than one..