Great find bro! I've got a fry's nearby. Not a bad price either. The description in that link doesn't say anything about IR or a reset button, but you say it does. If I don't like the feel of the controller, I'll just do what you said and swap the IR circuitry.
I did take the controller apart and found that the IR circuitry is part of the mainboard of the controller so it would be extremely hard if not impossible to seperate the IR portion of the controller.
I think the only sub-Logitech quality part is the D-pad. You may only notice if you play a lot of fighting games since that is the only time I noticed the diagonals would sometimes not get recognized.
*Note: The reset button only works on ver. 9 and above. The manual says this and I also tested it on a friends PS2. All DVD functions for versions below 9 still require a IR module.
BTW, your welcome!