There were no Kingswood panel vans in HQ-HJ. Sandman special vehicle package was available on all HQ and HJ commercials except cab-chassis, so you could option XX7 (which later became XU3) and the new style XX7 on the following models:

HQ 6cyl Belmont ute.
HQ 6cyl Kingswood ute.
HQ 6cyl Belmont van.
HQ V8 Belmont ute.
HQ V8 Kingswood ute.
HQ V8 Belmont van.
HJ ute (XX7 or XU3 not available on Holden ute after about 3/76).
HJ Kingswood ute.
HJ van.

Onec HX came around you could also get a Kingswood van, but as the XX7 and XU3 packages were revised to contain all standard Kingswood stuff there was no need to offer the Sandman package on Kingswood so you could only then get it on ute and van.