Keep an eye on the timing chain covers for the 22 series motors. When the chain gets old, it gets loose and the original plastic guide wears out-the chain wears a groove into the cover. If not a hole or crack. The newer replacement guides should be metal.
I used to agree with you, now honestly I say go with a complete Toyota Factory Set-up. If it goes 100K from them, I'll take another 100K worry free, and besides at that point the chain NEEDS to be replaced wether the guides do or not. I've also unfortunately seen too many sets of teh "High Performance" metal guides fail and screw up more than they were suposed to be "protecting" . yes the T-Chain cover will start to leak when the guides let the chain flail, but they're cheap and you need to take them off to replace the chain at that point. Having just gone through puting a new 22RE in my 894Runner adn then having a freak T-Chain Failure at only 500 miles I'm getting to be REAL familliar with these motors. Engnbldr.com is a great builder of these motors depending on what you want to do.
After all my searching and perplexing, and mostly after I decided I couldn't swing the 1KZ-Te Diesel swap I went with a bone stock 22RE and I'm not dissapointed. I'd love to have some more power, but honestly it's smooth like a sinnger sewing machine except for the typical "22RE noises" and once I get my gearing worked out and the new tires on it'll be more than willing to do what I ask it to do. To me it's fun to putter around in the thing rowing through the gears enjoying the "truckish" ride... I tend to chose winding through the hills and back roads here in Portland enjoying driving the truck rather than speeding down the freeway (unless I'm headed to work), that's how much I love driving these older toyota trucks (or just old trucks in general).
The key is coming to terms with the fact that these are heavy little trucks that are way over-built and powered by a 4cyl motor... they're not going to win drag races, and gearing is crucial. Stay away from the auto tranny's as, IMO, they pretty much sap what ever performance the older 4 and 6cyl motors have to give.
Any news on the truck for your son???
Cheers
Dave