Yes, it's possible to rebuild. Bring a wheel nut to a decent bicycle store, ask for a hollow AKA q/r axle with the same thread. If you haven't overhauled hubs before, get a pair of cone wrenches while you're at it. Read up on the procedure of bearing adjustment, then go at it.
Clean and lube while you still have the stuff apart.
If they can't find you a q/r axle with the same thread, then it gets more awkward. You'll need new cones as well. And they'll have to play nice with your dust shields. I'd hand the stuff over at that point, or look for another wheel, maybe do a trade-in if possible. Nutted wheel, being something of a theft deterrent, carry a value too.