The bolts I used were just standard ones from a local engineering supply shop. In the length I needed they ony had completely threaded ones. In the end I just bought the shortest ones they had with a plain shank on and cut them to length. One of my to do jobs is to find some better ones although standard black socket caps are higher tensile then normal hex bolts.
I did think of adding costs but the options are endless really. You could buy all the parts from Volvo, if you get them from the companies on the site you can get a fair discount. You have to consider the cost of postage, plus the cost of returning the exchange items.
While fitting these isn't as expensive as getting a complete kit from somewhere it still adds up. I might add some costs and a rough total once I have recovered from spending so much !
There is more info in some of the other threads and here,
http://www.volvoforums.org.uk/showthread.php?t=154501