Made by Adam Custom Cues. If I remember correctly, Richard Helmstetter, who is the brains behind the company, contracted with the family to make a production cue as sort of a tribute to George Balabushka. They started in the early or mid '90s, I believe, and still produce them today. There are several different models.
These cues have actually been passed off as originals by some unscrupulous people and bought by people ignorant enough to not know better.
I'm sure there are others here who know more about it than I do but that's it in a nutshell. By the way, as far as I know, George never signed any cues, at least not where his signature could be seen. I heard a rumor/legend years and years ago that he signed a few {read less than half a dozen} under the wrap but I don't think that's ever been proven one way or another.