Hi Rojo
I have some 10-32 x 0.5" C/S screws that you can have. The thread length is as stated 0.5", though the USA sometimes state whole length.
From my old days you are asking for ANF (American National Fine) not UNF (Unified) as UNF sizes are stated e.g. 7/16 - 20 UNF or 5/8 - 11 UNC. That is fractional diameter sizes (7/16" or 5/8") and not numbers to reflect a diameter (American notation for number being #). Therefore you presumably want a #10-32 x 0.5" (32 teeth per inch, for the uninitiated.
If you want some, let me know and I will post, need you address of course.
Regards
Jim