May also try... http://www.waltheramerica.com/ I heard they were under new management or new name, but I found there service far better than Earls. (Nothing bad to say about Earls, they just wanted to sell me a dime part for $25. plus shipping where the site I listed sent it out for free).
We are a gun selling company in Germany. We can offer the european style rear sight for the P99 for 6 Euro /each plus shipping.
We get these directly from the factory. [email protected] http://www.kaehny.de