About 3.5 years ago I was as DL for a week. I was staying at the DL hotel. I contacted the Concierge at DL hotel and they were able to provide me with a phone number for an off-site provider.
I do not recall either the phone number or the price, but it was in line with the WDW area prices. Also, you could probably do an internet search for the Anaheim area using "Mobility" or "Mobility Products" in the search engine.
If you are staying in one of the Disney properties then having an
ECV becomes almost mandatory; there is no transportation from the hotels to the parks.
BTW, you are asking about an ECV, not an EVC.