impeller for 2006 Suzuki DF140

[Campylobacter]

Hi, I feel kind of stupid starting a thread for this, but I am having difficulty ordering an impeller for a 2006 Suzuki DF140 (four stroke). Most of the usual suspect sites have one for a DF140 for years 2001-2004, but not the 2006. The manual lists part # 17461-90J01, but I can only find a few of these, and are all "New Old Stock"

A few questions:
Does anyone know if the above part number is correct and if they have changed it to a new one?
Why can't I find a aftermarket impeller?
Do you worry about "New Old Stock" impellers becoming brittle from just sitting?

Thanks in advince.