It used to be Koyo but apparently, as tim found out they no longer produce them.
He ordered some stark (think that was the brand) and they apparently had loads of slop/play in the caps and have been returned.
He’s just fitted some Matsuba, but yet to use his Zuk enough to form an opinion.
Bit of a lucky dip really. The standard ADK / Blue print parts from most factors tend to wear quite quickly, especially when used off road and driven through mud and water.
All i can suggest is to locate a local bearing supplier and go and see what they have.