Hal:

Any prop you want can be had from, or made by:

http://www.supercoolprops.eftel.com/

They are proud of their props, and this pride is reflected in their prices.

A far more practical source for three blade (and four blade) matched sets for counter rotating twins is:

http://www.zingerpropeller.com/index.htm

Three bladed wood props with metal hubs.

And you will find Zinger as "J&Z" as well as "Zingali." All the same company.

Hope this helps.

Bill,