Traverse linkage bearings

I’m planning for front fork repairing of my PX200 which have over 50000km on it’s speedometer. I’m trying to figure out which parts of the bike need replacing and which not.

There are two roller bearings between steering column and front linkage. It there some way to check out if those bearings are ok or not before starting to disassebly the bike? Like what kind of symptoms I should have if they are not ok?

It also seems that changing those bearings are very difficult thing to do, so could it be better to buy just new steering column with those already installed?