>> Can you get an actual EASA SPL in the UK yet?
Certainly - I have one (though you don't need one to fly in the UK till 2018). It's administered through the BGA, and there's detail about how to get one if you meet the criteria (basically Bronze badge plus cross country endorsement - no requirement for 50K I think, which is a part of the Silver badge). I'm not sure how much thought has been put into acceptance of other countries' licenses though.
It's my understanding (from someone who had this problem) that there's a rule that says that if you have multiple EASA licenses, they have to be from the same country - and since the OP said he had a UK EASA CPL, if that's true he'll need to get a UK SPL, so getting one in Spain wouldn't work.
But I agree with others - talk to the BGA and see what they say.
Paul