Sheppards' electronics bloke is good, the chandlery is still going, but everything else is pretty well dead or difficult and expensive. If you're set on Gibraltar you might get some suggestions from the Marina Bay port office (Karl, Brian or Johnny). Marina Smir's yard is good, very professionally run and not expensive. Not sure about what services are available, but no parts or materials chandlery - bring (everything) from Gib or La Linea. I have heard that Ceuta is good, but no personal experience. Sotogrande or Duquesa will probably sort you out, although at a price. I think Estepona's yard has closed . . . ??? although I don't know why. Cheaper and a bit tattier, Fuengirola has a busy yard and 2 or 3 chandleries (one English) neighbouring. They do paintwork - I've seen 'em at it. Make sure you get a firm quote before they start!