The bolts come out reasonably easily using a brass hammer and giving each a couple of quick straight on raps, or if you have the set-up you can use a press.For your purpose, the ARP set is overkill and if you had the rods re-machined, those bolts should have been installed prior to honing. If you install them now, the extra torque ARP wants could cause the rod to go out of round.
You could still probably get away with it(using the ARP) but you should be able to find a good replacement nut easily as it is 3/8 fine thread and many, many Ford, Chevy and Mopar engines used them. Just make sure it's a con rod nut as they are slightly longer and harder than the standard 3/8 nut. I'm just not sure how easy fractional sizes will be to get over there.