any Trek dealer on the planet can get them for you. You won't find them online though. But you can use ANY properly sized set of chaing rings from virtually any manufacturer on your cranks though. I've run both Shimano and Race Face rings on Bonty cranks with no problem. All you need to kown are whether the cranks are 4 or 5 bolt and the bolt circle diameter of the rings. Match em up and use whatever you like. I personally prefer Shimano cranks but have never been impressed with the durability of their chain rings. I'm currently running a set of XT cranks with Race Face rings no problem.
If you want original Bontrager rings you'll have to go to a Trek dealer to get em. Otherwise you can find just about anything else you want to use online or at an LBS.
thank you. that is some good info. i am still contemplating just changing the whole crankset but it's good to know i have so many options. i have no intention of paying top dollar at the trek dealer. i'd rather dig around online.
I had a Bontrager comp crank on my bike as original equipment but didn't really care for it, for some reason I experienced a lot of chain suck. Now I'm running a Shimano XT crank and I'm glad I did the change.