Welcome to the new Wizard Outboard Forum.
Working on a WD-4 - only missing pieces are the gas cap and grip.
http://store.oldmercs.com/product_p/36-23338a1.htm i think that this might fit IIRC
Cardiff torpedo grips in black are what you are looking for. Closest thing I've found to the original grip. https://www.motostrano.com/Cardiff-Torpedo-Grips-p/24271.htm
Doug Penn is another guy to try for parts. He may have a fuel cap and he carries grips. You want Mercury KD3, KD4 or Wizard WD3, WD4. cast aluminum tank caps. http://penn.itgo.com/ I forgot about our own Joe Poole at Ferguson Poole Marine. http://www.fergusonpoolemarine.com/ Joe has a lot of new old stock parts and may have a fuel cap.