yea they should be the same, I just typed in 88 chevy truck headers, and then lowest first on the drop down and went thru them. For me I made sure to find the ones that did not use the collector gasket, so they'd bolt straight up no welding or cutting needed.
I got mine from tuning pros for $122 shipped they have a best offer thing and that's how I got mine, $42 for shipping(which is dumb) plus $80 best offer price.
I think the ones you listed are for the oobs trucks since they claim to fit the older trucks, I thought the older trucks wouldn't fit newer trucks or vice versa, maybe I'm thinking shorties only, beaware because the newer style or obs are k1500 or c1500 not c10 or k10, if all else fails just ask them if they fit, they look like the ones we ordered for our 84 c10 though. I wished I knew they had stainless ones for that price.