Visit the Team Iceshanty Proshop
How about something like this from Sportman's Guide? You could cut a piece of plywood to set on top of a bucket and mount this with a swivel on it for comfort.Good luck,Matthttp://www.sportsmansguide.com/net/cb/cb.aspx?a=722615(Image removed from quote.)
toper...tried fleet+farm..they are on back order...I agree they look comfortable..
http://www.fleetfarm.com/catalog/category/fishing/ice-fishing/ice-shelters-furniture/polar-fire-folding-bucket-seat-with-back-restI saw this the other day and it looked mighty comfortable
This is what you need. It's mostly made of cloth but does have some support on the side. Mine has two hard plastic (or rails on the sides)(Image removed from quote.)\http://www.oakorchardcanoe.com/canoeseats.phpThey are made for canoes or camping. That one is expensive but you can find much cheaper ones around.
Mills Fleet Farmhttp://www.fleetfarm.com/search/71149 $25 Check it out
Saw the Polarfire seats in FF tonight. Honestly not impressed at all. For the money I'd spend the extra few dollars and go straight to the cheap boat seats.