What would you do???

Do you have a clamp to throw on that to slow the leak?

If so toss one on, but even without I'd drive it the 23 miles if you have enough coolant to keep levels up.

 

Tape it and go...I would.
20 miles tow, they can screw you $1000.

 

Yeah, definitely do not want to seize it up.

Mobile mechanic is a good plan then. Hard to tell in the picture how bad the leak is.

Hope it is a quick repair.

Joys of being and owner operator, been there done that.

 

Looks a slow leak, but if the rust is falling apart. I guess wait for the mobile mechanic. I would probably drive it you do have low coolant warning that should shut engine off when coolant gets low. If you have couple gallons of coolant it only 23 minutes or 30 minutes drive. You could drive 5 miles check coolant levels see how much is leaking at regular engine rpm

 

I give a vote to fill it and go if you can. You don't want to unscrew it while it's hot. You'll lose all your coolant. Youll need to wait a bit for it cool. Then you unscrew it slowly, you'll hear a hiss. Wait for the hiss to go away, repeat the process til you can take it all the way off. Then you can top it off.

 

Be careful. Of course, do not just uncrew it with one or two turns when it's hot. If you do it, turn it as slow as you can, and try to feel it if it is hissing. Turn off the engine first.

 

You could also leave the cap loose to keep the pressure lower until you get to the repair shop.