Best quality cartridge sealed bearings

Hi,
I'm in the process of building a new set of wheels with a set of Harden Track Hubs.

I'm looking for the best quality cartridge sealed bearings available on the market.

Does anyone know anything about bearings and a good supplier or what to look for.

Ideally I'd like a European manufacturer as I'm trying to build it as close as possible to original.

According to the below website the bearing code is KLNJ 3/8 Y.

http://www.classiclightweights.co.uk/harden-servicing.html

Thanks again,

Alex

Google is your friend, it looks to me as if the newer designation is R6 with a designation after that which gives you the sealing material/type.

Brand of bearing may help to tell if they are a decent quality, I tend to buy SKF or FAG but there are no doubt many other good manufacturers.

FYI even a "European" manufacturer might have the bearings made in a non-euro country. If quality is your concern, my view is that people living on any continent can make good bearings.

Thanks for the advice. I just wanted to keep everything European because the bike is from the 50's and back in the day everything would have come from the UK or Europe....or so I'm told.
I just wondered if someone had experience with the best quality European bearings.

ta