Welcome Local Newbie.
You can find this in Chevy/GMC trucks 93+. Usually you find them in 3/4 or 1 tons but they were available in 1/2 tons if it was ordered with the "MT8" option. I believe the diesel and big block ones are different (output spline difference?) so a small block gas engine donor would be preferred. The Dodge ones were similar except I don't think they came in the 1/2 ton at all. I believe the same deal applies with small block gas motor trannies being preferred over diesel or V10 trannies.
The recommendation above about the swap manual is a good one.
Pulled from AA:
NV4500 (1993-94): During the first two years of the New Venture 4500, Chevy offered this 5 speed with a 6.34:1 1st gear;
2nd 3.44:1; 3rd 1.71:1; 4th 1:1 ratio, and a 27% overdrive. It was also the first year that Chevy changed the bellhousing-to-transmission
bolt pattern. This transmission is ideal when converting your vehicle, providing an ultra-low 1st gear. GM, however, only produced
this particular ratio during these years. The major complaint of this 5 speed was stiff shifting and noise in 3rd gear.
NV4500 (1995): This transmission is identical to the 1993-94 transmission, except the 1st gear ratio had been changed
to 5.61:1; 2nd 3.04:1; 3rd 1.67:1; 4th 1:1 ratio, and a 27% overdrive. The noise and shifting problems had been corrected.
NV4500 (1996-2003): This transmission has the same gear ratio as the 1995 version. Chevy once again changed the
bellhousing-to-transmission bolt pattern and went to a larger bellhousing index diameter. This Chevy NV4500 has the same
bellhousing-to-transmission bolt pattern as the Dodge NV4500. These transmissions use a GM internal release bearing.
Dodge NV4500 (1993-2003): This transmission is the same as the 1996-99 Chevy version; however, the
only difference is the transmission input shaft, output shaft, and the tailhousing. The 2001 & up Dodge
transmission was changed to a 29 spline output shaft.
All NV4500 transmissions have a 12.375” case length.
(For more information on New Venture transmissions, order instruction manual NV001)
Good luck.