Dust and scratches (2nd update)

I'm being offered to buy some images which are scanned from slides. Some of them have dust and scratches on them. (Below is an extreme example.)
I've tried the 'dust and scratches' filter for it in Photoshop, but to get rid of the problem, the setting must be so high that the picture is totally blurred after. (One can use it partially, but it's a lot more work.)

I once used a scanner which had a filter which handled this during the process of scanning*. This filter was magic! It seemed like it removed all dust/scratches without noticable hurting the image detail at all. I don't know how the hell that's even possible (someone did, see comments.), but I'm looking for a similarly effective filter (Photoshop plugin or Mac standalone app) which can be used on the finished files. Does anybody know one?


* (Oddly I saw this on the computer of the guy who is offering me these images, and he showed it to me! It seems he omitted the filter on some scans for some reason.)

Update: it turns out, luckily, that it was a mistake he included any pictures like this, so maybe I'll be able to get them without those flaws, one hopes. (We'll see, I know he got rid of some slides after scanning for space reasons.)

Update: I was pointed to Dust/scratch software by Polaroid. After some searching, I found it here. The remarkable thing is that the software is no longer downloadable from Polaroid's site, but... it is anyway, via web.archive.org! I had no idea that this site also includes archives of hosted files! (And I would not have guessed it, since most linked images seem to get lost on that site.) This could be important.

(Philocalist: "It might be worth pointing out that the link you give is specifically for the Mac version; this page will give you the PC version, just click on October 15 2007 link on that page.")

... Below is my first try with the Polaroid software (in the PS plugin version). It is far more effective than Photoshop's filter. There's still some scratches left, but all the dust is gone with much less softening of the image compared to Photoshop, which is impressive. It would have taken a looooong time to spot all that dust by hand.
(Note: it seems the plugin did not work in PS CS4, but it does work with CS1. It's probably not tuned to Intel Mac software.)

... And just for completeness' sake, here is what I could do with a bit of fiddling, history brush, and such. A bit tiresome process, but then this was a very damaged picture, and without this software it would have taken at least ten times as much as the maybe ten minutes I used.