just go buy some cheap box a wine, dump the wine (if you are a wine snob like me) and then re-fill the bag after a very very good wash. i bought a 5 liter box at bevmo for $10. have stored xtol for almost a year in it and it is still perfectly good.
Just buy or get from a friend/relative a wine pouch with a faucet. Remove faucet (the hard part). Clean. Make a note of the empty weight. Fill with photo chemical; ensure no (or littel) trapped air; put back faucet.
I can buy those bags for $3/each at my local wine maker's supply... I may need to do that for my next batch of D76. That would be much easier to pour from than my accordion-jug... I'd still need to mix it in the jug though, I can't imagine stirring in a bag would be easy...
I've used Platypus bottles from Cascade Designs for years: supposedly their nylon/PE bottles are oxygen proof; not sure about the PE-only bottles. Since they were originally designed for hiking, they may be more sturdy than bottles meant to stay in a box; I've yet to have a leak and some of mine are over ten years old. However, they have a new model that contains a "silver-ion based anti-microbial" which could be problematic.
I also use wine bladders for my xtol that I bought at a wine making store. They were not very expensive. It shouldn't matter if the bag is clear or opaque, but I do store mine inside a dark basement and covered with a black plastic trash bag.
Interesting bit of discovery.
Check out "Lexington Container" Lexington KY web site.
They stock Mylar seal-able bags up to drum liner size.
Thought being if one had the handy heat sealer you could make about any size wine skin you might need for photo chemistry.
HOw to seal in the tube connection? Ideas please.
In my uni years I used the wine bladder exclusively as my chemical means of choice for storage. This worked really well until one of the silver layers deteriorated for whatever reason. I next moved to clear PET bottles stored in the D/R under darkness which has been far more economical as I no longer churn through wine in a box.