Yeah the same one specified by Aaron in his write up. (10mm longer than stock, part # 17380)
Remember to not limit your search to Quest vans, Villagers are the same thing
And after talking to Dan (Vengeful) the newer 125AMP units on 2000-2003 Quest/Villagers "should" also work.
Let me know it you need any more info, I'll try and take the bracket off this weekend and take some pics of it as I modified it. I really need to clean up the Alty better anyway. I'll also measure the spacer sizes again, I had them written down but can't seem to find the paper now. And again it can all be done with a hacksaw, metal file and drill. It's just a bit more work that way.
One other thing, you will need to space the pulley out too (see Aarons How To) I was able to get a spacer meant for alternators from a local parts store for free, they had a box of Alty parts and just gave it to me.. so it can't hurt to ask