Pretty straightforward stuff, you can get aftermarket actuators and remote keyless entry through any good parts store.
I found this company with a simple Google search Some of the sponsors of this forum also sell power lock kits.You could probably do all four doors for about $125 in parts and a day of your time.
If you have an empty key cylinder hole, just by a set of two cylinders for $40. The key will be different than your ignition, but you can still open the doors if the battery in the truck runs down. Or you can leave in the originals and just not connect the actuator rod to the key cylinder.