You probably dont need to go to the alignment shop. The camber is what it is....on a beam axle, the only way to change it is to bend the axle....not many alignment shops do such any more....the big truck shops might.

For caster, most people start with 6 degrees....top of the kingpin is laid back 6 degrees from vertical. Your tire sizes will affect caster so use the right tires. However, your caster is also set with the angle that the spring mount is oriented, your wheels and tires, and your axle. You can change it by a wedge in the spring mount, different tires, or by running into a tree.

Toe in is a toss up as to where to start. Start with 1/8 inch and drive it....add or subtract to see what happens...toe in is easy to measure and easy to change.