Welcome to the new Wizard Outboard Forum.
I think this might be what you are looking for: https://tillotson.ie/wp-content/uploads/2015/07/AJ-Series-Parts-List.pdf Your carb is in the first column after the part name on page 11. Apparently the carburetor is rare. I'd keep searching "Tillotson AJ45B" on eBay periodically if you cant find the part by number. -Bryan
THANKS Bryan! Great diagram.