They look like these wheels -->
https://www.hubcaphaven.com/p/499/al...d-9592558.html
Which according to the listing on that site, were originally used on:
Chevrolet Astro 2003-2005
Chevrolet Express 1500 2003-2008
Chevrolet Silverado 1500 1999-2008
However, I don't think the original center caps for those wheels are going to fit since the hubs on your truck stick out farther than the hub/bearing assemblies used on the trucks that originally had that style of wheel. Although you might be able to use the original style center caps for those wheels as a starting point and modify them to fit. Perhaps by using a hole saw to make an opening in the center large enough to clear the hub dust cap. Then see what you can find for a smaller center cap that could then be added to cover the hole and still provide clearance for the dust cap.