I can see where you're coming from in terms of value, but it won't be much use if you end up with the wrong prop - ask IBWET
As this motor is relatively popular, there are plenty of s/h props around for you to try for size (pitch). When you get it right, consider a SS one then. Personally, I'd stick with ally on a 60hp outboard, as the performance gains of a stainless will be marginal at that hp and there's a risk of damaging small gears in the leg if you happen to hit something with it.
Also be careful comparing props used on different make outboards, as the gear ratio may be different to yours.
Good luck - FWIW I'd try a 15" pitch first.