I'm free here
Yes there should be a ball bearing in the bottom,have a good look down there with a torch light or something in case it's stuck.
I've got some ball bearings here which I think were bought for an LPT,measure the diameter of the shaft and I can check them against that.
The LPT bearing is a completely different type to that the Funk Firm supply for the PT1/PT Too.
I have to say that my experience of the LPT is that the bearings are extremely well finished and very close matching with no slop.
Are you sure it is the bearing slopping not the platter rocking on the bearing?
Does the platter spin freely when there is no belt fitted?