Dave,
What kind of parking brake will you use in your truck? The foot-pedal actuated one, or the hand-lever actuated one? Most likely you'll be using the foot-pedal actuated parking brake?
Is there a hand lever assembly on your transmission? If so, you can take it off.
Is the foot-pedal set-up now in place? If so, just get a standard four-speed transmission cover?
Reproduction fiberglass covers are available, but I'd place an ad in the Swap Meet to try to find an original metal cover.
The hand-lever actuated parking brake was used on larger trucks (on some 1-ton and on 1.5 and 2 ton trucks) with the drive-shaft brake (propeller shaft brake).
