http://naturallyextractedtobacco.com/ (Go to extracts for a concentrate from American Spirit called Big Spirit.) You may want to start there. I don't have any actual DIY recipes, but mixing that premade Big Spirit with Hangsen RY6 at 2/3 BS and 1/3 RY6 is pretty close.
I was looking to buy the Ry6 concentrate, but still uncertain if Golden VI is RY6. I imagine it is.
No it is two different products. RY6 is under there HS line. Golden VI is golden virginia, which unlike the others brands I have tried is not bad at all. I haven't run across a bad Hangsen flavor yet but I have stayed away from menthol and licorice flavors.
That link is interesting!