Anywhere that sells the machines usually sell the Sunbeam rolls to make bags - ie any electrical appliance stores like Good Guys etc, but they're about twice the price of the Aldi ones. I've used both and haven't had a problem with the Aldi ones, but I've never bought the on-line ones so don't know about them.
DANBRI: There's a thread on here somewhere about the advantages of using them, can't see it just at the moment.
We keep a stock of frozen cooked meals and uncooked meat in them in the freezer at home, then if we're going away for a few days, just throw in enough for the trip and it's all sorted.
When we go away for long periods we take the machine with us. It can be kept somewhere in "deep storage" then every couple of weeks when we're in a big town, at a powered site, we buy meat, seal it up and head bush again.
But most butchers will seal the meat for you in meal size portions at a small extra cost - like 30c a bag or something. I've been to some places who advertise they will do it free if you bring in the add in the tourist magazine thing (stuff you pick up at the information centres)