Transfer case noise.

So I've noticed a noise coming from the front end. I jacked up the front and spun the tire and the noise appears to be coming from the output shaft of the transfer case. It's not a constant noise. Best way to describe it is a waw waw noise that gets faster as I drive faster. The shaft also seems to have some play. Here's the million dollar question (questions). Can I replace the output bearing without removing the transfer case? If not, how hard is it to replace the transfer case? Should I replace the entire case? It's a matter of time and money. If I have to tear apart the entire case, I don't really have the time for that (it's my only vehicle). I know people will probably say to rebuild the whole case. But again, I don't have the time for that. If I can just pull the front bearing that would be the best. It's an NP242. Also, any idea what the cost of a transfer case would be? Thanks guys.