Made in Japan's recommendations are pretty much right on the money on that one. You can purchase all of the parts you are looking for from the OE manufacturer for Volvo so there is no reason to either pay top dollar or compromise on quality. At list prices you are in the area of $600.00 for what you are looking at, I just did this entire job yesterday. The only thing that I would not consider replacing at this point is the serpentine belt tensioner. It is two stinking bolts to change that thing out yourself and they always make noise before they go. I have see one tensioner let loose and had the serp belt get into the timing belt and destroy a motor. That was the customers story at least and that is one instance since the white engines came out in '92. But, if you do not want to screw with it then step up and buy a serp tensioner and change it out while you are in there, you're going to have it off to change out the idler pulley anyhow.

Mark