I seriously doubt TAA ever had C180s in PNG but 18 Wheeler's dad will remember.
In the late '50's when C170s and C180s were operated in PNG, TAA were not operating in PNG, only Qantas and Ansett. When TAA arrived, the C170s/C180s had all but gone, to be replaced with C185s and later C206 and C336.
"VH SBU Cessna 185A -429 Ansett Airlines of P-NG PIAS 71 - N1629Z - Sold 27 Nov 1970 R Leahy"
I'm guessing here but I suspect this may be the C185 that Richard dropped into the lake in the island volcano (name alludes me), recovered and rebuilt the aircraft and I think still has it?
The Sunbird Services .... my introduction to PNG was traveling on the Sunbird Catalina from Port Morbid to Samarai. I heard that Catalina is flying again in New Zealand?