I would not think any reputable software supplier would still
be shipping it.
Be wary of any other source. Maybe they used the copy of X5
to purchase an upgrade so I think they would not be able to sell
that as they are still technically using it. That assumes it is a
genuine copy in the first place.
You may find cracked copies but apart from the legality, you
never know what you may catch from that.
Can your client not uninstall a copy they have and let you
use that?
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