Does anyone have a flying Sikorsky 53 in the Nam era search and rescue variant?

I spent nearly 1 1/2 years in the Qui Nhon Sub Area Tac Ops Center, about 6 months of it night duty where we often talked to and coordinated various units, including a few search and rescue efforts. Three of us made up the night shift, a Lt who was the assistant intel officer, a senior NCO and myself at E4 as the general purpose clerk, radio operator, gofer etc.
We had Special Forces with their mercenary units of Montagnards, Nungs and others plus some of those strange units made of guys in levis & hawaiian shirts who called each other Mr Jones, Mr Brown, Mr Green etc.

That is very interesting.
Thank you.
A couple of times groups of them came in and took over our radio room because we had pretty much the tallest antennas and best reach around. Except for the Armed Forces Network stuff on the mountain next to us, and they couldn't very well use AFN to run ops. Our job then bacame to guard them, keep the coffee and sandwichs in good supply and pretend we couldn't hear or understand anything they said on our radios.