Where should I go to get a bumper replaced while I wait?

While you wait, I don’t think so. Most body shop have a line of cars to be worked on.
I’m in NC, we just had an ice storm and the body shops are quoting February 1st before they take in any more body work. But try a MAACO paint and body shop.

If you can still find a phonebook, look in the Yellow Pages under bumpers. you will find what you are looking for, there.

I think what you’re looking for might be a bumper cover, not an actual bumper. Keep in mind if you buy that part new or aftermarket, they usually are black and need to be painted to match your car. That’s why it’s often better to buy these from salvage to match your car. I doubt any body shop would do it while you wait, but it’s worth asking. If not, it’s likely if you scheduled it in advance, you could probably drop it off in the morning and pick it up in the afternoon.