I thought the same thing. $100 SKS's isn't really the same as "cheap guns that work".Surplus guns are another story altogether. I bought so many cheap ones back in the day, wish I'd bought more. I remember the $75 SKSs of the late '90s, and 25 years ago I was buying Turk Mausers and Mosin-Nagants for $50 each. Not a lot of people seemed interested in them because they were cheap.
I have an East German Makarov that I paid &125 for, and an Underwood M1 carbine that I got for about the same price. $100 Tokarevs, Makarovs, and Nagant revolvers were plentiful. Even adjusted for inflation that's a bargain.
Unfortunately the days of cheap surplus appear to be gone forever.