It doesn't seem like a very common name in Japan, but possible, I believe. Young people these days are getting into using different names, so you never know what trends might come up in the next few years. "Ko" is becoming a rather rare ending for female names rather than being practically standard like it used to be. Now it's more often "e" (ay) or "mi" or "ki" or "ka" or maybe "na" or "no".
I personally like the name Sora, but it can be used on men too. It is more common for females to have this name but keep in mind that it can a guy's name too.