It might be an idea to list your requirements on this site; they will advise you if a prop of your spec is found :-
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NB.
Extract
"The standard original prop on the Columbia 45 was a 20" X 13 pitch LH three blade . The standard engine was a Perkins 4-107 (45 hp) or 4-108.(50 hp). The optional engine was a Perkins 4-236 (85 hp). The std prop on the 85 was a 13" pitch or an optional 14" pitch. A few of the last 45's built had an optional 6 cyl (100 hp) Chrysler Nissan diesel.They all used a 1 1/4" shaft."