Try contacting Assistance Dog United Campaign. Google it! They do a voucher program for things (chow, kibble, vets, equipment) for working & currently in- service dogs. So you dont get cash but instead a voucher based on specific need of your animal. They seem to have a network of vendors & suppliers across the US that accept their vouchers (like vets) or ship the dog foodstuffs, heart meds, etc. I think a couple of the big foundations (like Doris Duke foundation, Rbt Wood Johnson) support ADUC.
Good luck!
Go to the upper right corner of your screen, you will see SEARCH SITE. Type in "service dogs" and search.
As for funds, I would suggest you contact the Alzheimer's website.