Could one of you who has an original WIn PRe-64 300 H&H verify the length and muzzle diameter for me?

Thanks for your time!

They are 26 inch. Muzzle dia is the same as a 30-06, 270, etc if you have access to one of those. They have integral ramps for the front sight unless very late. The year and 300m should be stamped under the chamber area.

One word of caution is a lot of them have been rechambered to 300 Wby and some to 300 win Mag. There were a very few carbines (20 inch) and they all had integral ramps for the front sight.