Wondering if anyone can help me find out the bolt size for my truck. (1998 F-150 XLT.)

It lives 4+ hours from me in Tofino, BC and I live in Victoria, BC, so measuring is tough and I'm hoping to get new bolt(s) asap so I can get the truck on the road again before May long weekend.

The rear leaf spring has snapped and I got a replacement part from a wrecker but I'm gonna need at least one new bolt I think. It's not the spring on the drivers side but it still doesn't look like I'll be able to get both out without cutting one.

I've enlisted a friend (who I'll owe lots of beer!) To help me with the swap out while im out of town and need to get the them up to him by mail.

The new spring from the wrecker has the rear hanger, and I'll be hopefully able to reuse the ubolts, but do have a replacement set on hand but they fit a little weird.
(which is what I did when the other side snapped on me).

There's a fastener shop not too far from me I could have new bolts fashioned but I need to get them the size...

 

I recently replaced the leaf springs on a 1997 F Super Duty and this website was very helpful. Very happy with the springs as well as the hardware purchased there. Look up the springs for your truck and they should have the matching U bolts listed as well.
https://www.autoandtrucksprings.com/index.php?p=login