OK... one more question....

These filters of which you speak- I'm having a hard time finding them. I usually shop at KEH. I know I need a B50 size filter, but I don't really see them in their Hasselblad/filter section. If I meander around their site, I can find B50 red and yellow and green (which I have...), but as far as a B50 IR filter- no luck. Are you'se guys familiar with this site??? Can someone point me in the right direction???