@treeslayer2003
For the past several years, I've been buying all my handles at the local logging supply store. The brand they sell is Tennessee Hickory Handles (tennesseehickory.com). I'm happy with them...vertical grain...good kerfs...pretty sexy.
You could also try House Handle Company (househandle.com) or Whiskey River Trading Company (whiskeyrivertrading.com). I haven't bought from either, but I've read mostly good things. I'm planning on ordering from Whiskey River at some point. They're the only place that I've been able to find straight handles for camp/boys axes and hatchets.