Searching for a fuel container to carry 18 oz in my caged bottle holder, I found this:
Spare Fuel bottle 530ml for S9 stove - eBay (item 180549657533 end time Sep-18-10 09:09:53 PDT)
Ya can't beat the price! The competitor's cost was $17.95 each, but you had to buy two to get free shipping. I paid $5.95 each, which included free shipping!
The containers arrived in 7 days. They fit tight enough in the holder to scrape its paint off.
To keep pranksters from stealing this bottle or contaminating the fuel, use a plastic tie-wrap to secure the cap to the seat tube.
Loop the tie-wrap several times from cap to tube. When it's time to remove the fuel bottle, snip the tie-wrap close to its latch. That way, you can re-use the tie several times.