Back in April of this year, JCThornton released an original Krystal model and rig for free! This is a more cartoony style, in keeping with his other works. I think it's well done, and the fact that it's free and available in multiple formats makes it that much better. Even native Blender for those with constrained budgets.

You can download the model directly from his Patreon and read about the development on his DeviantArt post. Oh, and he posted about it on Twitter too.

JCThornton also made his rig available for SFM and GMOD.