AER remanufactures the majority of them....including Ford. I located my engine (after a LOT of research) and had a Ford dealership owned by a friend of mine do the install. It's going on 30k miles as of today and it has run perfectly. I would recommend upgrading as much stuff under the hood as you can afford while the engine is out. That's what I did and it's almost like a new truck.
I'd highly recommend searching on the Ford150 forums. I totally renovated my KR and learned an awful lot on those sites.....and still do.
I agree with this, new plugs, coils, belts, hoses, water pump, fan clutch, cylinder head temperature sensor, engine mounts, radiator, new coolant, exhaust manifolds and gaskets, upgrade to doorman studs, if it doesn’t come with intake manifold gaskets and oil adapter gaskets, you’ll want to get some good gaskets like fel-pro brand. If you can replace the injectors while the fuel rail is out, I would do that as well. Most of these parts you can source on the aftermarket for a really reasonable price, rockauto is always a great place to start. The intake manifold and the oil adapter are about the only things I would reuse. You can also get a good drain on the front differential since there is space to get the cover off of it with ease.