Is that the one from Rolly's auction in Melbourne last week?
I can think of a Military Range in SA where there are 4 concreted into the ground and have been there as long as I remember. I'll have a look and see if the elevator arrangement is still on one for you.Didn't realise you hadn't seen one. I just had a look to see if I had a pic that showed more of it. This is the best I have on file. It stands just under shoulder height for me, the legs have a spreader bar around them about 10 inches above the ground. The legs have sharpened points ... the bit drawn in red is what I'm missing- it's an elevation screw set up. If anyone knows where I can find one... it's a left hand thread inside a right hand thread. Turning the knob extends or retracts both ends of it, raising or lowering the elevation.