I've got a rear wheel bearing on the way out on the 89 340 GL, anyone any ideas for the best place to get one? and is there just one type fitted to the last model years? I see fro a quick search that there are a few different types.

Plenty on the bay last time I checked. It shouldn't cost you more than a few beers either

According to Haynes all the same on 340+360 after 1986.

The lastest system was similar to that used on the 360s before hand, but with no additional seals.

I think you may need a press to remove and replace the actual bearing. The last time I attempted it I could not find a local garage to take them out and the dealer just said they had to 'burn them out'. I replaced the hub from a scrapper instead.