Google is perhaps the best place to look for mirrors of older software versions, though they could also be demo versions which are expired. Same goes for any re-sellers or distributors who may have hosted the software themselves.
Any use of the software will of course have to be in accordance with the applicable license conditions it comes with. If V309 is a "Home Use" version it may require re-activation every 30 days or so, and if there are no re-activation codes being released for older versions you're at a bit of a dead end.