As a 60 size plane probably none at all. I try to get about one inch of clearence between prop and ground. My last build is a trike geared plane, my first one, I have always built tail draggers. I have about one inch of clearence and haven't had any prop strik problems so far but maybe using a Master Airscrew prop would be in order at first? I use MAS for trainers where I know there will be a lot of strikes and so far haven't broken any.
My plane was built from plans, a 60 size pattern plane and I bought the longest aftermarket frone LG as I could find but it just said 60 size on the package. Can't remember the make. The stick should be OK. Look up the specs on the plane and see what they have for clearence, you may need some bigger wheels/tires? Or you can use a three blade 14X7.