if it's for the rears, then it is possible to get kits of the slider, pin and springs. i've had them from High Street parts shops but don't know if they're available from Renault.
it's worth bearing in mind that these (rear) calipers have been used by Renault-Peugeot-Citroen on *a lot* of different cars for well over 20 years now - so you needn't necessarily be asking for a Renault fitting kit