I recently had to change out my ballast impeller due to normal wear (even through the green one had no visible wear, the vanes felt loose and it wasnt working well)....I use these frequently dumping and filling all the time with lots of different riding abilities.

I put the new orange one in from wakemakers and it works great.
Unfortunately the replacement ballast impeller does not include the o-ring.
I was able to find the o-ring at pep-boys and i wanted to share this information with everyone.
Fel-Pro 35669 Thermostat O-RING SAAB V6 3.0 1995-2001
$1.50....and I am sure if it said marine on it the part would move a decimal to $15.50....haha.