Tried to get something like that from Social Services for my mother. We were told she could apply for a grant if she used a wheelchair but not if she intended to walk as a ramp is too dangerous in icey weather. So provided you promise not to walk on it, Social Services may be worth a try.
Hi we have Millercare near here..(pretty sure they have website) they do ramps that go in cars not sure baout for steps, but if you google ramps for mobility scooters..or! if you have handy man about .you could possibly have one made.not sure if you intent to lift or move it or is it a permanant fixture. good luck