I found only two hatcheries in the country that carry Jaerhon and only one of them, Ideal in Texas, carries the pure bred Jaerhon. And it seems that they only carry them from February through a little past Easter. Beyond that, you need to locate someone with a flock who is willing to sell hatching eggs or chicks. There are several here on BYC who were willing to sell me some hatching eggs before I found that Ideal was carrying chicks this past February. They were shipped to me in the middle of that horrid polar vortex and arrived in fine health.
Two things I forgot to mention about them: 1) they are sex link chicken, so you know what you have right when they pop out of the shell, and; 2) they take about six months for egg laying maturity.
While I was there looking at your Jaerhon chickens, I found the Red Shoulder Yokohamas. So pretty. Now they are on my list but of course they are rare and no price is given.