A Technics SP10 Mk2 (without plinth) was £450 in 1976. That was a seriously expensive deck back then and that with Matsushita's advantage in terms of economies of scale. I'll bet very few were sold to anyone other than radio stations until they introduced the Obsidian plinth.
Had 'em at the beeb for Radio 1 'cos they could instant cue - 0 to 33.3 in 1/20th of a revolution or something bonkers like that . . .
No Obsidian plinths; they would only have used them for chopping coke.
Cheers, H