i'd do that before you go to an engine swap, the surpercharged toyota engine is just below par for my 5.9L jeep i had which was the 4th fastest jeep ever made behind the str-8 series and the 5.7L hemi, that being said it should be more than enough for any reasonable means.
you really don't want to swap the engine out, you'll be alot happier with a completely tricked out truck with w superchargers than you would be with a truck with a sweet engine but none of the other goodies.
the supercharger you use is straight from the Tacoma trd's, i checked with my dealership and the price was about the same as i've seen around the net but i was just dreaming about doing that and didn;t look to hard
so if i had 10K i'd do this, in this order (note i said i would)
-supercharge -3K
-3-4 inch lift toytec or ss 1.3K
-tires 1K
-sliders 2oo
-arb front bumper or shrockworks 800-1.2K
-winch 400-700
-gears 4.88's 1K
-hood scoop -400
-powder coat my rims 200
-sick double din head unit 1K
-cb with whip 600 with custom install (i have a sick idea for this)
-ok ok new paint job 1.5-3K (for it to be done right and maybe something trick)
and then your over the 10K but i think that's a pretty good basic list to work from, now just google 4runner and whatever you're looking for from up there and it should be easy enough to track down.
-and this if i did get a new paint job..who knows how much and do you guys think it would work for wheeling? lol,
http://solutions.3m.com/wps/portal/3M/en_US/Scotchgard_Paint_Protection/Film
also what do you guys think about recommending aftermarket hd control arms or a sas swap?