Old audio cassettes. (Top Amersham HP6)

I'm trying to get hold of some examples of old audio cassettes - the ones shown are typical and probably date from the 70s or 80s. I realise that a lot of these will have long since gone to landfill, but if you've got a box of them in your garage that you keep meaning to dispose of, I'll gladly relieve you of them! I'm more than happy to collect small quantities or to take away an assortment and rummage through them for items I can use. I'm mainly interested in the graphics used and the variations in how they were manufactured, so the condition of the actual tape doesn't really matter (and any secrets about your tastes in music back then are safe with me!). Thanks!