FWIW
In my experience be wary of anything loaded with Winchester ball powder.
I was doing a lot of pig hunting up to about 1985 with a BSA 308. Loads were 748 at best accuracy so not extreme with 150 gr bullets. Some didn't get used so got stored in a cupboard in the shed.
Fast forward to around 2010 and those loads in the same rifle would blow the primers.
Back in the Axes thread I mentioned the situation with axes in Oz in WW2.
Pre most of ours came from UK or USA. Both supplies largely cut off by the war.
Our local steel maker BHP and a local axe firm Hytest worked out a steel formulation that cut out the forge welding of the blade step.
IIRC from an article on these and collecting from the 1980's
IH didn't make everything. So any with everything stamped IH has been got at.
I had a Springfield one with a XXXXXX serial number and a barrel marked SA 3 42.
Lost it in our "purification campaign".
Did you use all 4 or just 2 bolts? If just 2 and they bent then then you'll likely go OK with 4. I'm presuming that if you can make another nut you have the gear to make a plate to hold them?
Would be good if you could thread the holes to hold everything down but that will depend on how hard the nut is - there might be a language advisory if you happened to break a tap off!
My 2 cents worth.