Sorry to take so long to reply - just picked up the question.
The one in the photos can be ordered from the old beek for $AU600
I'm just on finishing mine which is a bit heavier slightly different design ( in the base area) materials around $90 (some secondhand scrap) $50 of bits and pieces (bolts, shackles cable), a free gift of a hand boat winch worth about $100 welding materials and time ( about 3 weekends)