When I first moved to SF, there was an electronics surplus store on Market Street, near Van Ness, across from where Twitter and Uber and Dolby are now. There were surplus places all over. I liked Mike Quinn, in a huge quonset hut on the Oakland Airport property. Stuff was piled to dangerous heights, and prices were negotiated on the way out.
We used to go the the Foothill Flea Market before dawn, then hit Haltek, Halted, maybe Weird Stuff.
The price of Silicon Valley real estate killed off the urban surplus places, and ebay killed off the rest. And the ease of getting cheap new parts and test gear from Digikey and Mouser.
And, I guess, the fact that fewer people want real parts and test equipment.