[AmityvilleHams]

I'd definitely agree on the Fitch(of course that's not an option outside the UK so it doesn't really work in this situation),but I'd avoid Harry Hamster.It has artificial dyes(although not specifically stated on packaging or ingredient lists,but it has been confirmed)which are best kept out of the diet for any species.

An alternative substrate for this particular situation would be hemp.Hemp is not the ideal substrate but it is less likely to cause allergic reactions than wood substrate,and while it probably isn't as good for burrowing as something like Fitch it can be an economical choice and would be much preferred over any wood substrate.