Andrew,
I got these off Ebay. They are the same as I have on my XT225.

http://cgi.ebay.com/ebaymotors/1-Han...Q5fAccessories

but when I searched Ebay just now for "XT225 risers" I also saw these which I might try next.

http://cgi.ebay.com/ebaymotors/1-up-...Q5fAccessories
Since they go up 1" and back 1.25".

Why don't you try them and report back? Might make it easier for my old knees to stand on the pegs.