Isobutane canister shaped bottle for alcohol fuel

You could take any HDPE container of the desired diameter, cut out a middle section, and (plastic) weld the two ends together. I'd jam the two ends together so there was a little overlap and a bit of a mechanic connection, then dibble molten HDPE along the seam. The only equipment you need is a pair of scissors to cut the original bottle and then to cut the waste pieces in to thin strips (1 cm wide or so). Light the strips on fire with a Bic lighter or a match and let the molten HDPE dribble onto the seam. Once it has cooled (hardened), you can shave or sand down any high spots. Check for leaks and repeat as needed.

I’ve been looking for this for a long time too, David, have you tried it yourself, what do you use for a top?  What HDPE container have you used?  I’d love to hear more about it.

Just found some time to putter in the garage.  I used a very thin-walled drinkable yogurt “Kefir” container – tall and 1-liter capacity to start.  I cut it down a LOT in height and welded the seam.  44 grams and 11 inches tall to start.  21 grams and 4.5 inches tall when finished.  I’ll start a separate thread under Gear, MYOG and include photos there.  For OP’s application, I first thought, “hydrogen peroxide container” and I’m still thinking that.  HDPE.  A little thicker wall.  Cheap, really cheap (a loss-leader during hunting season at a buck each for the liter container).  Tall, cylindrical, with a flatter top than most drink containers, so there is less wasted height.  Or, of course, my favorite – dumpster-diving at the recycling center and seeing what catches your eye.

Round Christmas coke bottle fits perfect in a snow peak 700.