It all depends on the gear ratio Of your gearbox. As well as your needs. Let's say the gear ratio is 2.58. If you want maximum traction, then a 3-blade propeller with a diameter of 1700 mm (67") is better. If you want high cruising and maximum speed, then a 2-blade propeller of the same diameter is better. If the propeller diameter is limited by the clearance, it is possible to use propellers with a diameter of 1600 mm (63"). In this Case, you will lose a little at the start, but you will win in high-speed flight. Of course, sabre-shaped blades are preferable. But straight blades are cheaper. The quality of execution is the same, and resource restrictions are removed. You're lucky. You have my favorite plane .
Yes. We started production of extra strong carbon blades and hubs SAE-2 and SAE-1 at the urgent request of American operators Lycoming and continental.
The most common sizes are 1644 and 1755 mm (saber-shaped blades).