Contact John Folke on Ebay that makes gaskets for old outboards.
I just used a set that he made for my Evinrude Zephyr, and they
were very nice, and an exact fit.
If you are going to work on old outboards making gaskets from stock is a given. Tools needed are a sharp pair of scissors and a set of gasket punches. Stock for sealing gaskets is available at auto parts store. Gasket stock for making heat resistant exhaust gaskets is not commonly available. Technique and Skill come with practice.
Agreed, gasket making/cutting comes with the territory. Don’t recall off hand where I purchased gasket material for the exhaust manifold but it was readily available.
I use punches, sissiors, nail trimmers & clippers, exacto knife, box cutter, and a dremel to smoothe edges. ( haven’t stabbed or cut myself yet).
I almost always figure out how to use the casting(s) involved as die cutters. I just lay the gasket material on the part involved and go tapping around the edges with a small ball pein hammer, and use the ball side to create impression marks where the bolt holes are so I can use gasket punches to create the hole.Once the gasket is installed, if there is a lil bit of overhand visible, an Exacto knife takes care of that with surgical precision. Hope this helps.