Excerpt of electronic calculators at Sears, in the Spring / Summer 1975 catalog.  High-resolution scan should accept zoom, so you can read small print.




And for comparison shopping, Staples had this 4-function machine for $4.00, which had to have been less than $2.00 in 1975 dollars:

But then, I'm down there and see this one, for 99 cents.  It has to be some sort of promotional loss-leader item, for even the Chinese can't be doing this:

It's Moore's Law or its corrolaries, taken to the ultimate extreme (how many doubling times might 32 years be in this technology...).