Chaz,

If your step van harness can be replaced with a pickup harness, Classic Parts' set at $199 should be a good one.

https://www.classicparts.com/Wiring-Harness/products/124/

That link also shows a few "cut-to-fit" kits.

Same quality/type harnesses are available from Jim Carter, Chevs of the 40s, and other old truck parts vendors.