I have grown both 'Arakawa' and 'Ibo Kan'
@William N. Valavanis Bill V is absolutely correct on his ID.
'Arakawa' has a warty bark, with STRAIGHT needles, no significant twist to the needles. Needles are slightly shorter than 'Ibo Kan'.
'Ibo Kan' has a pebble bark, and has TWISTED needles, every needle twists along its length. You can see it, if you look at the ''white stripe'' of stoma along the length of the needle. The needle twists along its axis. It is visible even on young shoots that are too young to develop the pebble bark. Needles are slightly longer than 'Arakawa'
The bark of the two does look different in trees more than 10 years old, but the difference is more subtle than the difference in the needles.
I have never seen the 'Nishiki' cultivar of JWP, so I can't comment about that.
I lost all my JWP after a health issue 12 years ago. Don't know if I'll ever get back into them.
I also tried air layering 'Arakawa'. After 4 years the air layer still had not formed roots. It developed a small disk of callus, but never developed roots. I would be cautious about air layer attempts. Make sure that the placement of the air layer won't leave you with a dead mother tree if the air layer fails. Not saying it is impossible, just saying it likely is not easy, not 100% guaranteed, probably less than a 10 % chance of success. I have not tried recently, my last JWP air layer attempt was more than 10 years ago.