1956 es2

https://shop.nortonownersclub.org/big-end-assembly-all-singles-1933-1963

Out of stock?

Try Paul Norman, ouch:

https://racingnorton.co.uk/epages/4c675e64-813f-4c0a-8926-87a680c962a0.sf/en_GB/?ObjectPath=/Shops/4c675e64-813f-4c0a-8926-87a680c962a0/Products/%220863%20A2/27%22

Aren't Alpha Bearings still trading? I hope so, for the sake of old bikes everywhere.

... website is still alive and shows Norton single big ends. Worth a phone call. I believe they were taken over (by Autocycle?) some years ago but kept trading.

http://www.alpha-bearings.com/