Just to tack onto your original post. I remember rebuilding a 161 with my dad in the early 70s and I remember that was the first time I saw a fiber timing gear. In the late 80s, one day I was out driving my J and it just quit for no apparent reason. I checked the fuel, none being pumped. I checked for spark, none. I knew there was one common component which ran both the distributor and fuel pump and that was the camshaft. The engine turned over with starter just fine so I knew the crankshaft was turning. It told me the crank turns but the cam doesn't. I remembered that fiber timing gear and how I couldn't believe it would turn the cam. So... I pulled the distributor cap and turned the engine over and I noticed the rotor was not turning. I knew there was only one thing that could produce this set of symptoms! Upon pulling the front cover off the engine it was quite obvious! At that time, the gear was $6.50 at NAPA.
In all my years of owning this car, that was the only time I ever had to walk because of it. I should note that those fiber gears are quite reliable for the most part. Yours is the only other one I've heard about in all my years in the hobby so they have a pretty good track record.