La Scuderia Rossa seemed to have most of what I wanted but their prices were, to put it mildly, rather high.
I ended up buying nothing from them, they wanted a total of £2,500 for the grab handle, a used side air intake
, and the plastic oddments box (fitted in centre console) They wanted £3,000 plus shipping for a radiator, and £3,000 for the aircon compressor.
I guess if I was rich I would have just given them my credit card number, but I'm not.
I got the oddments box from Ferrparts for $40 and the handle was £30 from QV London.
I repaired the air intake, and the radiator was re-cored by a specialist for £200. The compressor cost £250 to rebuild.
Before throwing money at new parts, make sure the old part can't be repaired! This sounds obvious but a dealer will often just replace faulty compressors etc without looking at this. For instance a major Ferrari dealer in the UK did not know that there was a repair kit for the heater valve, saving £300 on the cost of a new one.
Maranello Classic Parts in the UK are very helpful, and Ferrparts are also excellent. Maranello have a lot of "Classic" Ferrari parts that are not catalogued, which means they have stock but can't find it! They bought large quantities of parts from Ferrari and it's all sat in the warehouse. If this happens ("we are showing stock but the computer does not give a location/bin number") try Ferrparts as they clearly have more clout and seem to be able to get Maranello to search for the parts.