bearings - I usually knock out the original bearings and take them to an industrial bearing supplier - they measure and match.
I always ask for sealed bearings, to protect the bearings a bit longer if the main water seal starts to leak.
You should find buying bearings from a bearing specialist instead of a washing machine spares place will give you the same part for much cheaper, and if you choose brands well you could get better quality too.
For example, I have just done bearings on a (modern) LG front loader.
The bearings were $40 each as a spare part, but I bought them for $7 each from a bearing shop and I got SKF(German) bearings, I reckon better than the Korean originals.
Roller bearings are usually supplied in 3 forms - open (you can see the steel balls between the inner and outer rings); shielded (a metal cover over the balls on each side, to keep dust out); and sealed (a rubber seal at each side to keep dust and moisture out. The sealed ones cost only little extra and I reckon makes a longer lasting repair. The more expensive genuine spare parts were only shielded, not sealed.
The main seal is another matter - some are standard oil seals you can get from the bearing supplier (cheap) and others are specialist sizes or are carbon counterface seals which are specific to each machine. I haven't looked at a Servis spinner for over 10 years so I don't remember what type they have, sorry.
