My Wife worked for Boots in the late 1980's and we bought 2 of their "boom boxes" for my kids as well as 2 portable colour TV's fantastic quality and were still working nearly 20 years later when the now adults finally moved them on.
I think the Cassettes were Sharp under the hood and the TV's Toshiba/Tatung but I could be wrong as I never had need to open them up.
I had a Boots audio cassette care kit that I used for years cheaper than buying IPA.
I suppose I need to go looking for my AIWA now
Cheers
Mike T