An old 70s film listed in the BGAFD database is Arabian Knights
with two unknowns, NK0501 and NK0502, but their photos are
awful.
There are some excellent photos from this film in the newsgroup
alt.binaries.pictures.erotica.pw-series, added today I think.
They seem to be taken from a Rodox magazine, Rodox 65 I think.
Worth adding to your Joe King 10 web site maybe.
There seem to be six girls in the film and you only mention four.
You can see these pictures at web sites:
under Samples
Guilbert