> I'm started looking for some still available in sales channel but not too many
> is available. If any then others are in unconventional sizes [...]

Note that the ARIA is a COM Express module so needs an additional carrier board.

> All of boards referred here in HW list here are EOL or ?

You mean the list on http://www.morphos-team.net/hardware? If so, yes, all of them are out of production. The Sam460cr has been the most recent board.