I saw one with that many miles when I bought my '13 two years ago (which had 152k on it when I bought it). It depends. That's a lot of miles but you have no way of knowing if it was babied or abused, cruising on the highway under the speed limit or straining pulling a trailer up and down steep grades, if it was serviced early at every interval or neglected (obviously some of these things you can find out from records but just saying, unless you drove it yourself you don't really know).
I figure I can get 300k easy out of the engine/transmission in mine, and expect to have random shit come up along the way like xfer case, diff, etc. But 99% of it I'll do myself with the help of the forum, and I enjoy twisting wrenches as much as getting it sideways on a wide sweeper. So it's up to you if you're willing to do or pay for things as they come up, the tradeoff is you have a lot of leverage to drive the initial cost down. The trucks themselves are solid, have some common issues that are easily addressed, and are well worth it in my opinion. I'd get another one if I could heh, actually more like "when" and not "if"...