Hi Mark, sounds like a great buy. Not much repro stuff in 1964!
Following on from Nev's comments, yes, it was likely unchromed. You should be able to find out from the factory records.
If you have bits of paint that have been covered since new, you could get these colour matched at a good auto paint store.
I did this when I found original paint under the badges of a mid 30's Hunter - the red was a lot deeper than later Ariels I have seen. While I haven't done much with the bike, I guess the colour is preserved.
PS, no matter how good the motor looks, take the crankshafts out and clean the oilways. They fill up with gunge and cause major problems.
'51,'56 Squares, '48 VH, '27 Model C, R67/2, Mk IV Le Mans, '06 Super Duke and Ariel projects.