So I was just randomly looking on eBay and managed to find this pair it's the momotaro X blue owl 12 overdyed.
I have the original pair( on the right) for some time now so you can really see the colour comparison.
Pair on the left is the Sumi ink dyed that I wear for work 5 days a week, supposedly they will fade to blue but I feel like it might be a few more years until I see it.