I don't think anyone makes a half door model any longer. They will have a full door and a full back seat, not a comfortable one but still a full seat.
Most trucks on the lots will also have a short box 6' and a bit longer, although now I think it is called a standard bed.
Dodge will probably give you the best price, but lowest payload.
When I was looking Ford was the proudest and I didn't really look at GM's.
Expect to spend 23 to 27K. Go shopping the last week of the month and look at 2013's for the best deal.