Three New Guinea squatting figures 1950s

I have grouped these three interesting figures together as they seem to represent the classical  “three wise monkeys,”  known as the “see no evil, hear no evil, speak no evil” monkeys.  They were collected on a trip up the Sepik River in the 1950s.  The three figures are mounted on a custom wooden block. 

height of figures excluding the block 15cm   Overall height 20cm 

Please view the photos carefully as they make up an important part of the description