I came across this Ad being sold on EBay which I have not seen before. It was for sale for £2.99 so for that price I bought it as I thought it was a very nice poster for this unit which was advertised as the smallest Walkman the size of a Cassette itself it is the WM -20 but a Gold Edition and what is interesting the Ad does not refer to the Model of the unit specifically. It simply refers at the bottom of the Ad to it being Gold. and the smallest unit . The model number is however visible on the side of the unit in the stack of cassette tapes https://www.ebay.co.uk/itm/Sony-Sta...694375?hash=item44407cc327:g:BpMAAOSwQGVdG46n
My little WM-10 is gold, I don't think it was a special color but yea, this series is so cool, the compact size was drool-worthy when they came out. It was a popular model when it came out but it was still expensive when new.