I'm thinking WF3 would work best, but especially on a reel suited for that weight. I don't know of that many situations in Colorado stream and river fishing where you need to cast a whole spool. I've found 40 or 50 ft is about max although there are a few places I've yet to fish.
A friend of mine from Australia brings his every year when he comes out and it's pretty cool. we joked about using a fly reel on it but didn't try it. Says it packs with his carry on luggage.
Another thing I'm seeing is all the Tenkara fishing rods are telescopic, although they dont use reels nor have guides on them.You might still want to look into that technique for it as well.