I have a weirdly specific question about a UK product: can anybody point me to a source – a book, a catalog, anything – that will tell me when exactly "Walkman" branded second-generation TPS-L2 units replaced the original "Stowaway" branded ones? (The later model has "Walkman" in silver instead of "stereo.") It's part of a long research project, and it'd be very helpful if I could know when exactly these came out.

Thanks!

I'm sure I have see a TPS-L2 with just a blank space where the Walkman badge was to appear on the later version (I don'tmean that the badge had fallen off!) "Stereo" was embossed in the outer casing as with later version. Maybe there were many subtle variations of the TPS-L2