I went to Vintage brake in California on a recommendation from my vintage racing friend's. I thought I'd give him a try. After all, he builds brakes for all the top name racers in the country.
My 73' has a 24 inch clear coat stainless line $28, AN-3 fitting 3/8-24 chrome, $5.95 and one AN-3 Bulkhead fitting 3/8-24. $7.95 plus shipping.......
Mike can also sleeve your norton master for a better feel and performance ......
Vintage brake, Sonora, California 209-533-4346 or look him up on the web.
Tim_S