Nick - Those "4810" casting number wheel cylinders are correct for your truck. Below is a screenshot of the vehicle application list from Raybestos related to this casting number. The casting number was a standard used by numerous aftermarket replacement product companies for this particular size of cylinder and range of vehicles.
On your note concerning the age of the flexible brake hoses (2 front and 1 on rear axle), I think for safety sake it would be wise to just replace them. They may look great, but like any other rubber type piece are subject to aging.
One another related thought. Did the brakes have fluid in them throughout? If not, there's a good chance the master cylinder and wheel cylinders will need to be inspected and rebuilt. Any moisture in the air trapped inside them could have caused corrosion and stuck cups and pistons.
