I assumed a gunsmith, but I was hoping somebody might know of one who had a Mauser action wrench handy, or perhaps just someone on this forum who had removed their own barrel once before.
It could be done by any gunsmith with the correct bushing for his wrench. About any gunsmith who works on centerfire rifles would have what's needed.
The barrels are usually bolted down on a heavy bench or I beam using the bushing that fits, then the handle is bolted to the receiver. Not likely a smith would loan one out, but there shouldn't be a problem of finding a smith who could do it for you.
Barrel action wrenches are available from Midway and Amazon. I watched some videos on You-Tube and ended up making my own. Saved a bunch of money and worked like a charm. Held the barrel in my hydraulic press between 2 blocks of wood. Make sure your wrench fits the front of your receiver.