I know many places to get parts. Some things to consider is #1 it should have an iron head on it, if it has the per-unit aluminum head on it they tend to crack between the valve seats and head bolts, it is possible to put a 9 bolt head on from the 60s.
#2 Primary cases in decent condition for those are hard to come by.
#3 If you want original headlight parts, those are also very hard to come by but recently they have started making repop fiberglass versions.
Mechanical parts are easy to get and others can be had but you will PAY for them and are not readily availble. I have a connection for magnito and generator parts too, those are also hard to find. 53 should have the mag and generator not an alternator.
