If you move to a new (different) rim you may need new spokes if the ERD of the rim is different.
I think you can get a new CR-18 rim for about $35. You can try to do the replacement yourself if you're somewhat ambitious (I was able to do this with nothing more than grease, an electric screwdriver, and a spoke wrench, but ymmv) or pay a mechanic not a whole lot to do it for you. If you elect to do it yourself this is the cheapest option, I doubt you can get a quality wheel for $35. OTOH if you're having a mechanic replace it for you, this could cost as much as a new wheel. Then again, a new wheel will probably be machine-built and if your mechanic is good the quality of your hand-assembled wheel will be higher.
I would replace the rim, either myself or with a mechanic. That's just my opinion though.