We have resealed hundreds of those boxes. The bearings are available but the only way to fix the play between the reciprocating ball collar and shaft would be to buy a whole new assy. (which would probably cost more than a MB rebuilt box - if they sell them).
The play in the bearings is adjustable so if you have done that properly and still have major play then get a used box. I have seen maybe 3 worn out boxes in near 30 years of MBs and two of them were on 190s.
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician
[This message has been edited by stevebfl (edited 04-21-2000).]