Recertification is a state controlled affair, so there's really no telling what your particular state does. But in many states, you can recertify any cylinder that meets the standards of recertification, which do not directly include age.
But by direct, I exclude matters like the OPD valves. If your cylinder does not have OPD valves, and they are required in your state (they probably are), you can have the valves replaced.
But, of course, you can just buy new cylinders. There's no such thing as a standard price, so do lots of shopping around, including online. Aluminum tanks are super nice, of course, but they are quite a lot more expensive than steel ones.
Lynn