Argos is, and has been for a very long time, a High Street catalogue shop in the UK. Some kind person has scanned some old catalogues, so I was moved to look for some of my favourite things. And lo, we find slide rules, electromechanical calculators, and also electronic calculators, co-existing, in 1974:
From 1977, a Commodore offering, as well as scientific calculators from TI and Sharp. I do remember the TI-30 from my schooldays.
For more on Britain’s Argos stores, see the comedian Bill Bailey: