Here in California I have found inexpensive stabilized ground flax at both Costco and Sam's Clubs.  Generally it is 3 pounds for about $8.  Not every Costco or Sam's Clubs have it, so you may have to ask for it.   I have no idea if it is available in other parts of the country or Canada. Yes, this is human grade flax, so very safe with no additives. I hope this helps with the often high costs of our metabolically challenged equines. Anyone else have any other cost tips?