I am 6'2" and have no trouble getting in and out of my 83 C20 with stock bench seat. I had the seat rebuilt with denser and thicker foam so the seat is higher than stock height, but I can still enter/exit wearing a baseball cap (but not a 10 gallon cowboy hat.)
I plan to eventually install a pair of 2001 Chrysler Sebring seats I have. They have integral seat belts, so you can avoid the seat belt issues with old square body trucks. Chrysler Sebring convertible seats prior to 2001 have an ignition interlock feature, so I would stay away from those.
The best seats I have owned were Recaro seats (not Recaro racing seats.) They are about $1200 per seat now (plus shipping and sliders) and you provide the mounting, and can easily go up to $4,000 and more - so not easy or cheap but worth the price if you have the $$$ to spare.
Here are some links to the Chrysler seats and some "cheap" Recaro seats
http://www.ebay.com/itm/01-02-03-06-...pXMXXP&vxp=mtr
https://www.vividracing.com/catalog/...4523_9891.html