If I recall from a recent trip to Spain there are a few 67s working for RENFE? They are classed as 334s so I'm not sure whether or not they were built specifically for Spanish services or transferred from the UK as 67s.
The Class 334's are not Class 67's, although they have visual similarities and share the same GM engine and some other equipment.
The 334's were built to a RENFE requirement and apparently use a lot of equipment inherited from earlier RENFE locos.
Most of the Meinfesa/Vossloh Espana diesel locomotives use similar body profiles that have evolved gradually with each model. (note the family resemblance in the Euro 4000, EuroLight and class 68 UKLight)
The Class 67 was specified by EWS alongside the Class 66, as part of the large order from GM's EMD division, following the establishment of EWS.
The requirement was for a 125 mph loco to replace the ageing class 47's being used for EWS's former RES work; i.e. the mail trains.
The construction of the class 67 was contracted out to GEC-Alstom's Spanish division (Meinfesa), who had a long history of building EMD based locos for Spain, Europe and other parts of the world.
(n.b. GEC-Alstom's Spanish business was sold to Vossloh in 2005)
The 67 is basically a class 66 power plant shoehorned into an GEC-Alstom (Meinfesa) Bo-Bo body shell, with alternators, traction motors and gearing to suit the different requirement.
The body shell used for the 67, is the same basic design and is very similar in appearance to the Israeli Railways
JT BW24 freight and
JT 24CW passenger locos built by GEC-Alstom (Meinfesa) before the class 67.
Only 30 class 67's were built and non have been exported outside the UK (so far).