Sandline
The O-2's at Honiara are not connected with Sandline.
They arrived at Honiara late DEC 1997, with a Hughes OH-6A, and, as you say, one was constructed out of the two. The chopper is still there, but don't have an update on it. They all sat in the containers for years and came directly from USA.
The Sandline is a Cessna 337, not an O-2 version. Just painted to look like military. (I have the rego's somewhere in a box) There was talk the PNG Govt was to get the 212 a/worthy for Fishing Surveillance in 2004 ?