there's a zillion options- and it depends on the end use of the truck. Are you looking for show or go? If you plan to drive this thing at all, ESPECIALLY off road, there's no way I'd sepnd more than a few hundred dollars to have somebody else do it. I spent $2800 to paint my truck Lemon Glow yellow, it's the worst investment I've ever made, that includes the money I lost in the stock market. Sure, the truck looked damn good and I got compliments, but I couldn't use. I didn't dare drive it hard, I spent every weekend detailing it, etc. I slowly watched my expensive paint job get eaten by the ozone and chipped by rocks, and then I rolled it.
Then I flat-greened it and never looked back. You can get good results with spraycans with the right prep, I did both my trucks for about 18 cans each.
I had to scuff the yellow truck for the paint to stick, but didn't prime. After it had set for a week the paint is pretty tough. For the deuce I didn't even prime, just washed the truck and sprayed. Went on smooth, except for the spots that had been brush painted before.
It's better thoguh to get it by the gallon and spray it with an airgun, it's something you could do with little work, the flat paint especially is very forgiving. Touch up is easy as pie also
Or, I'd suggest taking the paint down to some place like Macco after you done the prep and degreased the prior paintjob and just have them spray it. For a truck that size with you supplying paint I'd guestimate a couple hundred. Remember, it won't be perfect but you have to decide what you'll live with.