I've just rewatched the then Sci-Fi Channel miniseries adaptations of the first three Dune books and they have some elements which could augment a SD edit rather well.

I found myself enjoying the second series (with all it faults) much more than any of the PT films BTW which proves to me that obvious CGI is not the main problem the PT.

The Doctor Who special Planet Of The Dead has a lot of real dessert footage which might be worked around (the story itself is bobbins so using bits from it is possibly the best thing going for of it).