Both Hobby Easy and BNA Modelworld stock AC Models. They are pretty much the only ones that have regular stock but they can still be hard to get. Once a set goes out of stock, it’s typically 6 months or more before re-stock happens.
AC only releases full sets of figures, never individual ones and they seldom even break sets up in to two. Expect this 8 figure set to run in the $125-150 USD range.