Three of us bought SEM off you Taily, Shags, Phil McGuire ( a helicopter pilot) and myself. We paid K10, 000 .
At least that was when K10,000 Kina was worth Aus$13,000. Today K10,000 will get you Aus$4,200 - if you can find a bank that will accept it.
I doubt one could generalise over Missionaries, there are good and bad. The LMS brought education and health to the Papuan coast over 140 years ago. The Catholics provided good educational and health services, particularly on the New Guinea side. The SDA's at Kabiufa provided high quality secondary education. The Sallies at Badili did great youth work.
But I recall on one occasion we were hauling Twin Otter loads of bagged cement into a Yank run mission station out of Mendi. The Mission house was excellent. The Church good and substantial. The one room school and the small Haus Sik were Kunai huts.
And the cement was being used to make garden edging and steps up to the Mission house.