Those figures are just guesstimates. I think paid about $13-18 per filter depending on whether they charged me a $250 processing fee, I just can't remember. I know there was a $250 dollar processing fee but I might have bypassed it by spending $500+ dollars, so maybe I only paid about $650. I looked at the box in my garage and I bought these back in 2004 so it hard to remember all the details. Good news is I was able to track down the wholesaler and I have attached a link for you. I could check my reciepts to give you an exact number, but that's not really important. What is important is how much are they charging in 2010. Call them and see what they say. I looked them up and they still have 225 filters but they still requiring you to buy a minimum of about 50 filters. Currently they have the PH6353 filters listed for $12.23 plus shipping. I would guess you could get them for about $16 each with shipping if you are willing to buy 50 or so at a time. Hope this helps and sorry if that was confusing. Spence

http://www.surplusparts.com