JapanFlyer....

....I guess the "load charts" are real nice, and the fancy foot work is cool.
The problem is, the crazy prop numbers don't exist, at least not at my
hobby shop. For general sport flying the 6, 7, and 8 pitch props are used.

Walk into your hobby shop and ask for a 10.5-14 prop. (yeah right )
Tell them some Guys on the Internet said you should use that prop.

Dave.