I got a vintage Wards hand plane for Christmas, found in Cottonwood AZ.  All the parts seem to be there (badly painted/finished, but fixable).  The one piece that I'd really like to replace is the machine screw for the front handle (but if I find the handle screw, I betcha I can find the tote screw too).  The machine screws are #10, 20 tpi; that second value is the problem.  I checked local Ace Hware, and it's definitely #10 (smaller than 1/4, Not metric; fits into #10 sockets for about one turn--24 and 32 tpi sockets).  I did find a 1/4-20 bolt to confirm my threads are 20 tpi, and I checked some wood web sites:  no go.  Suggestions?

Maybe @steven newman can chime in on this one.

 

Don't know if this site is any help-

 

http://www.tttg.org.au/Content/Stanley Planes and Screw Threads - Part 2.pdf

a 10/20 machine screw is mil spec...

https://military-fasteners.com/screws/machine-screws/AN503-10-20

Try some metric screws.

Can get both bolts at nhplaneparts....Eric has a "store" on ebay....you can even contact him, and see if he has the correct sizes for both handles.  Wards usually were made by Stanley.