Plus 1 for Ronnie's.I use Ronnie's for part numbers
Link
Ronnie''s Harley-Davidson''s
Ronnie's Harley-Davidson® offers service and parts, and proudly serves the areas of New Ashford, Windsor, Lenox and New Lebanon.partsfinder.onlinemicrofiche.com
that looks goodThis one works
Genuine Harley-Davidson OEM Service Parts | Harley-Davidson USA
Purchase genuine OEM Harley-Davidson service parts from Harley-Davidson. Search by make and model to find nuts, bolts, clamps, and more.www.harley-davidson.com
nothing there for a 1971 from what I can seeRonnie's still works for me.
One great resource of knowledge.