and by "old" i mean a few months. I would like to replace my front wheel with one that has a machined side wall. My front wheel is the stock IRO. Would it be wise to sell that wheel and buy a whole new front wheel or buy a rim and reuse the stock IRO hub? Is there much demand for just a used rim?

You could buy a new rim and keep the old one around for whatever reason, but I doubt anyone'd buy a used rim. If you're selling sell the wheel.

Well i guess what i should have asked is, does it make sense to do that financially? or would i recoup enough by selling the old wheel to make it worth it to just buy a whole new wheel.

there is the labor cost for your new rebuild. its better to sell the wheel, get 75% of the money you need for another new stock IRO machined wheel. thats what i would do.