Finally getting back to it...

Been away for awhile,but now I'm dragging my little boat out for some work. I've been injured and out of it for a bit but I can get around some and mess with it a bit. Still trying to get an idea of how old this Allison is. Any Ideas anyone? There's no HIN#. Previous owner had it registered as a 1964 Duracraft. I just want to have some idea as of age. Pretty sure its a R 15. I'm starting to collect parts and try The old boat. Thanks in advance.
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