For Alignment tool, I would refer you on this SeaDoo forum with link "/inexpensive-engine-alignment-tool-diy.73567". I can't post full link because I'm too new to posting to this site.
Given SBT tool out of stock for a while, I did this and it worked...about $50 for parts, just need a tool to cut round stock in one place. It works; made a big difference.
For Shims, I bought some off Amazon...little pricey but nice. I tried SS washers and they are OK, but little tricky to remove.