I need your help/opinion

[Keystone Chevy Man]

Hello, I am brand new here. I actually just found this page recently. I am looking at buying this 1972 Chevy K20 Cheyenne. Over all it's in pretty decent shape. My only concern is this two piece top. I've never seen anything like it. Appears like the top is removable. The doors have been cut across the top. I have no idea if I will be able to find new seals, weather stripping etc. for around the windows. Has anyone ever seen this before? Help! He's asking $4,600 which seems pretty fair for the overall condition of the truck.

Thoughts?

Like I said, I am brand new here. I've never done a forum before so if there's anything I'm not doing right please let me know! I'm all ears. I have been totally consumed with looking at all the amazing threads showing different builds. Great stuff and a wealth of knowledge.