So I had one of these box sets years ago and sold it off for a move, recently I found the other box and wanted to watch the series again.

Seems that both have the same episodes and also part II.

Yokai ningen bem: Special Collection [MSL-10001]

Yokai Ningen Bem (1968) [BBLA-9017] minecraftle game

Some info on the part II that I found, this was not available when I posted the first box and the second box has the same episodes.

From MAL:
Youkai Ningen Bem: Part II
For 1982 a 26-episode TV series sequel to Youkai Ningen Bem was planned. Because the original producers disbanded, the animation was done by Topcraft. 2 episodes were created and the project shut down without airing on television. The episodes were released to the public on a LD-Box Set a decade later. 2,000 units were printed and all were sold out.