The steering rack was unique being modified from a standard rack but I don't know what it originally came from. Modifying an early 2.2 Mini rack might be a good way to go.
The uprights were Dicks own fabricated design - similar but not identical to those on Peter Bove's car. The hubs were Vauxhall Viva. I wouldn't go for the original Girling braking system. Wilwood parts are much better and reduce the unsprung weight
The steering column was bespoke.
It was fitted with Dellorto DHLA carb.
I wouldn't worry too much about originally as the cars spec evolved over the years even running a straight cut Quaife Chevette gearbox at one time.
Martin