TRY THIS!
I've had this problem before. Not on a 4Runner, but at least on a toyota. Your calipers are most likely fine. And I think if you would get a "loaded" set it wouldn't fit your problem anyway.
Here is what you need to do. Know I don't know the exact way the calipers are put together on a 4Runner. I just got mine and I haven't done any brake work. But usually the caliper is held on by two bolts. And the caliper floats on these. The bolts actually goes through a small tube called a slide or sleeve. And the caliper slides on the tube. There is a little boot on each side of the caliper, a pair at the top and bottom. If anything these might be riped. If they are replace them. When ever you do a brake job doen't just replace the pads. Take the caliper off too and check the slides. Pull them out, if they are really pitted replace them. At the very least take them to a wire wheel on a bench grinder to clean them up. And then lube them up, I know they make a special lube for this, I can't remember the name. But this is what make pads wear out, and brakes drag and squeek, it is usually not the pads. Hope this helps, or gets you going in the right direction.
