David - my guess is that MOST dealers would rather sell you one. Bigirons is a little different, and I think he'd be open to help (for a fee naturally) - but he's also in Madrid which (at a guess) is a bit far from where you're looking. There will be loads of bilingual gestorias on the coast.

type "importacion de vehiculos españa" in google - a huge list of companies importing used cars etc to spain