Sorry about the slow reply. The part number for the conventional tonneau cover is 38-3040 and it costs $279.95. The cover that hinges at the front with lift struts is 38-3080 and costs $399.95.
Hope they are what you are looking for,
Scott

Scott Ward

2 1948 1.5-ton Loadmasters
The red one and The snow pusher
1 1950 3100
1 1955.1 Chevy 6500
1 1954 Chevy 6500 2-Ton
1 1955 1st Series COE 5700
1 1963 K20 (454)
1 1964 C10 (350)
1 1951 1.5-ton Dump Truck
1953 and a 1956 Ford F800

Raising a teenager is like trying to nail Jello to a tree!