Our Township has an Emergency Management Dept. They have generators that are given out when needed. My husband is signed up with them because without his hearing aides he is deaf. So if there is an evacuation they know there is a deaf person in our house. See if you have a local or County Emergency Management.
Make sure your power company knows that you live on oxygen 24/7. They have programs to make sure vulnerable people get O2 and priority assistance if there's a power failure. You might also contact your local fire department's non-emergency number and let them know, too. They might have a similar program or work hand in hand with the power company to deliver oxygen to those who need it.
Of course, the spare tank is a given, too, so get one.
I don't know of any programs that help with a generator, but when my husband was on 24/7 oxygen the last 22 months of his life, he was given a large oxygen tank to keep on stand by, that he was to use in case of a power outage. Did the folks that supply your oxygen not give you one of those just in case? If not, you may want to ask them bout that. Best wishes.
Of course, the spare tank is a given, too, so get one.
Buy an oxygen tank in case of an emergency. They're not expensive.
I would suggest calling your local government or senior's department to see what programs might be offered in the community for assistance.
Probably not, so you will find it difficult to get aid in buying it.
Find out what you really need and then you will have better luck getting assistance.