Hi Mike
I'm sure you'll be able to find a lot of Mk 1 5 parts fairly easily in Portugal - now that the UK is no longer in the EU, a lot of R4/5 parts have become difficult to get hold of. There must be a lot of NOS stuff in France, Spain and Portugal - I used to find a lot of parts on French/Spanish eBay; there's a lot of stuff on Leboncoin and Milanuncios too.
Some (emphasis on the 'some') R4 and R5 parts are the same, depending on the model - balljoints/front (but not rear) shock absorbers/some brake parts, etc. Some parts that seem similar are different - steering racks, for example. It's the usual small Renault minefield - you must have the PR900 parts book to be sure.
In the UK, R5 body panels, windscreens, headlights and some exhaust parts were harder to come by a few years ago than their R4 equivalents. I've got a few R5 bits and bobs, but they'd be easier to find closer to home.
Good luck!
Encuentra aquí los repuestos originales para tu renault 5 o renault 7
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Retrouvez toutes vos pièces pour votre Renault R5. Produite en 2 générations de 1972 à 1984 à presque 5 560 000 exemplaires. Ses différentes motorisations iront de 782 cm3 à 1430 cm3 et de 34ch à 160ch. Son nom de R5 vient à l'origine de la TL avec son moteur de 5cv fiscaux. La Renault R5 sera...
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