I owned a KLR 2008 model too. It has 60,000km now since bought in October 2008. To date, I have done a valve check (all within limits), change spark plug, flush and replaced coolant but no bearing change or doo hickey. Yes, the bike does eat up lubrication oil a bit depending on my speed along the highway. Other than that the bike works flawlessly. However, in Malaysia where I lived, the KLR is not a popular dual-purpose bike may be we do not go off road often. Just my opinion that is.
As for spare parts, I do not know how to help you out from here. The KLR is manufactured in Thailand and Malaysia has a big market for Kawasaki bikes. By far, it is the cheapest bike in Malaysia. So, parts not a big problem here.