This is only my opinion, based on my experience with "building" engines of various V-8 configurations (building meaning performance built), working my early "pay my dues" years in different speed shops / machine shops, and my quest to gather information about my own options when the 3.no go lets go in my own truck.
Many moons ago I had an '83 22R in a pickup...and in seeing how "rebuils" are done at a cookie cutter shop (assembly line rebuilds), I decided that it would take a couple extra bucks, and some extra time, to do one myself. Seek out a reputable machine shop that does hot rod work, has a dyno (will explain in a sec), and offers performance parts from good companies that are not domestic/import specific (Manley, and so on), and have your base block done the way you want, for your intended use... rather than by a generic set of standards. Concentrate on the basics which a lot of people overlook, and most of the time think "it won't matter that much". I'm talking about balancing...cc'ing, and all the measurements that won't be done to a stock motor.
Pick the camshaft (or have one ground) to suit your needs...specific. Take the time to make the head breathe in the RPM range you want...not what Toyota has done for the masses.
"If Huffy rebuilt engines...would you buy one? Or would you call Specialized?"
Long story short...you will be farther ahead doing it yourself, plaus the added benifit of knowing every nut, bolt, and quirk the engine has, and chances are when you reach the inevidible point of really dropping the hammer on it...you'll know exactly what it will and more importantly won't do.
