What engine is swinging that prop? If you take the spinner off and look at the hub, the size of the prop and the engine it was made for are usually written on the hub.
The makers of wooden props are usually pretty good at matching their props with the engine/airframe. Aymar-DeMuth produced some excellent props. Bernie Warnkie made one of the best and, by my standards, prettiest props in the business. Sadly they have both gone to the Prop Shop in the Sky. I was the lucky recipient of one of the last props Bernie made. He called it his "Almost-Constant Speed Prop" and you can actually feel it grab as cruise speeds are approached.
I do not remember there being a redline on the prop itself. I think if it is properly mated with the engine, engine redline should be a good reference. Someone who is still flying an Aymar-DeMuth may know a little more.
1946 C-90-8 J-3 Cub
The adventure begins when things stop going as planned - Glen Heggstad