I know they used to be. Got my very first amplifier scratch & dent for $175. It was a 40 x 2 Alphasonic and it sounded a helluva lot better than all those Power EQ's peeps were using(1982) and blew Alpine's first amplifier offerings away as well.
It was kind of a neat lil amp. You couldn't bridge it but the way it was designed all you had to do to get 80 watts to one channel was disconnect one speaker output(found that out by accident) which was easy cus it only had 3 speaker wires, one common ground and R/L positive.
There weren't any user friendly connectors like we have today. All the wires including power and ground went to a 9 pin molex plug which really didn't bother me. Firstly I didn't know of anything better and secondly the total spectrum of my install kit included a knife to strip the wires and a roll of electrical tape(crimp connectors? what are those). If I hooked somethin up wrong it was a simple matter of unwrapping some sticky black tape and untwisting a bit of wire.
Well I have no idea what kinda stuff they make today altho they were fairly cuuting edge at the time. They were one of the first to offer a class A amp. never listened to one but I heard they were very good. The 65 x 2 they had was way out've my price range at $400.