Been hearing metal-on-metal like squeaking sounds from my front right wheel well for a couple of weeks. It started off almost negligible and now it's nearly continuous; although, I don't hear anything when I'm on the highway doin 70. I'm suspecting a wheel bearing issue. Since I can't get it in the a shop till next week, how terrible is it to drive on it for another 200-300 miles before it gets replaced?
I agree this sounds more like a brake pad issue than a wheel bearing issue. The main reason is, with a wheel bearing issue, you will feel it more than you'll hear it. When the wheel bearing is bad enough to hear it, it's to the point where it is a true safety issue and you shouldn't be driving it anymore. If it were the wheel bearing at this point, you'd only be causing damage to other parts of the front suspension by driving it more, so you'll be creating more of a repair bill.
The brake pads have a part on them called a squealer. This part is designed to make noise when the brake pads get down to a certain thickness. They only make noise at slower speed (or you just cannot hear them over road noise at higher speeds). It would be easy for you to take a look at your front brake pads to see how thick they are. As long as the brakes are not metal on metal, you could drive the vehicle without too much of a worry WRT to safety. If they are metal on metal, you need to get it taken care of.