These are pretty in-demand items. One will occassionally show up on APUG, but not too often. If you need one quicker than that you might try making an offer on this one:
The initial asking price of $325 is high. These usually go for anywhere between $150 to $250 in a regular auction, depending on condition. I paid $189 for mine at auction a number of years ago. It was in near-pristine condition similar to the look of this one. I also got the original retaining band, which is not always included.
I justified the amount by realizing it was a once-in-a-lifetime expenditure to acquire the correct tool for the job. And with care that tool would then be available to me for the rest of my life. When considered in that light I don't consider these to be overly expensive.
(Note: I have no connection with the seller of the above item and no interest in his sale.)
Ken