Single player EM + obscure Spanish manufacturer = extremely niche market. Maybe £600 or so non-working IMO but there might be some specialist collectors who’d pay more.
Hard to accurately tell condition but from that picture the backglass and cabinet seem in reasonable condition for a 50 year old machine. How is the playfield?
Would be more marketable if you can get it working. I can see the machine is showing TILT, if nothing happens when the start button is pressed I’d guess that the ball count step up unit (normally in the head, but I can’t find a schematic for this machine) needs some attention and that once that’s cleaned up and moving freely you’d have a better chance of the reset sequence starting cleanly. Of course there could be myriad other issues, score reels might need adjusting etc. but that would be where I’d be looking first after reseating any Jones plugs.