Need Screw thread size for rear sight axis screw?

I am mounting a PH5B rear sight to my M1917 Enfield and need to know the thread size for the rear sight axis screw which screws into the mounting base of the PH5B rear sight? does anybody know the thread size for the screw?

Thanks

--fjruple

Edit: I understand the PH5B target sight used a longer rear sight axis screw than the standard rear axis screw? does anybody have any idea where I can get the longer version? Or do I have to make it.

Fjruple, Per the Stratton book it's a .10 dia. x 56 TPI screw. Length is 1.28 inch. Salt Flat

Salt Flat--

Thanks!!

--fjruple