I am not familiar with any "Japanese Silkie". Although they could be Japanese Bantam X Silkie.....Some of them seem to hold their tails up a bit, and there's single combs.
Thanks for your input. This is helpful. They are cute little hens. At least two of them are laying. They are a bit skittish. We're working on building a bigger run. We currently have a 12 x 4 run that extends from the coop. It is only three feet high. Once we have something taller I will be able to go inside and get closer to them. I think they will become friendlier then.