@ninaspears what quantities and how many sorts? Of course "Food Grade" extends way beyond the substrate. The companies specialising in this have invested millions in technology, infrastructure, certification, etc.
However, even if your quantities aren't vast, that is not necessarily a problem. We're in the UK and have sourced relatively small orders of this nature, always bolted onto the end of someone else's 'large' orders, when the appropriate tooling is set up. You just have to allow a longer lead time, otherwise the set-up costs to run a few thousand bags alone will be commercially non-viable.