There are parts available through all the usual vendors to replace the missing body parts. Cabs are a dime a dozen on the salvage market. That being said, you better have some serious welding skills and a strong work ethic. Getting it on the road soon is not an option at this point.
Welcome to the Stovebolt madness. There is no cure! shake

Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)