I own several classic cars including an old Ferrari, MGB and Lotus.
You should never feel you would be left on your own.
I have organised parts for RR owners all over the world that have not been able to source parts.
Even one owner who owned an old Chinese eye RR in Australia I sourced Piper window parts for him that are extremely rare and when limit switches were not available I found suitable alternatives and shipped these over.
Many forum members, me included will be happy to 'giveaway' parts to help keep other owners cars on the road.
You only have to search member Robert S (wraithman) and look at what he has achieved on his RR restoration.......it should be in a museum.
I do a lot for friends and club members and don't even charge....just ask they give a donation to an animal charity......and perhaps a bottle of whisky for me.
You will not be short of any support, but again it starts by buying right, as a bad purchase can cost a fortune to put right and end up costing more than paying the extra for a well sorted car in the first place.
I am always open to a few weeks working vacation if adequately kept fed and liquified..........