I am not an expert and have never listed Aboriginal artifacts like these.

However I have looked at quite a few current and ended listings under Colllectables /Cultural Religious - like yours a pokerwork animal, and some grinding stones, and they do not appear to have any more authenticity than you have - "deceased estate." One specifically said "Previous ownership unknown." So I am not sure why you think you would be unable to list them.

If you have some reason to suspect they are quite valuable, I would suggest you take them to a bricks and mortar Auction House - most would have a tribal expert who could advise you. Good luck.