lots of options, using both new and used parts
172 cup setup, about £450 for eveything new inc alternator, or get it from a breaker. Also need to mod or change one PAS pipe
Laguna 1.8 8v (maybe 2 litre also) essentially the same as the cup, but uses older style wiring on the alternator, £100-£150 from a breakers???
Volvo setup same alternator as the laguna but uses a pressed and lazer cut steel bracket. Alternator and PAS pump sit in the same place as cup setup. About £40 for the brackets from a breakers yard, or ~£70 from renault if you can work out which model they are used on (saffrane maybe.....) plus an alternator