Norton es2 1939 main bearings

Good evening

I m restoring the engine of my es2 1939.

Have a piston, rings, valves etc

But now i want to replace the main bearings, one ball and two roller bearings.

c3 fit

When i ask people and when i read about it they tell me to place the ones with the c3 tolerance.

Where can i find them(originals) or are there good (quality) replacements?

for example: 

https://www.vintage-motorcycle.com/en/parts/norton/norton-roller-bearing-crankshaft-1-lip-rl10llrja1-c3-nke-austria?destination=/en/search%3Ffulltext%3Dcrankshaft%26page%3D4

Allmost all other english bikes use also the c3 fits on the main axle.

But not as easy to find for nortons as it seems...

So use not RHP but replacements ?

Or use rhp standards?

Thanks

Dirk