Hey nucopia, I made some classifier buckets out of 10 litre plastic buckets with not quite all the bottom cut out (eg turn bucket upside down then cut a circle out just smaller than the size of the bucket bottom so you have about a 10mm - 20mm lip. Then I cut a piece out of bread crate to fit inside the bucket, push it to the bottom and screw it to the bucket. This works to classify to 13mm - 14mm, if you want smaller classification then I have various sizes of punch plate to drop in the bottom of the bucket. Will post a pic when I get home.
P.S. I second the Garret Super Sluice Pans. The main difference to other pans is the riffles sink into the side of the pan not poke outwards from the pan. Hopes this makes sense.
Cracka.