If it were me, I'd just culture the yeast from a bottle or two of kellerweis. That's what I've done in the past for beers with unique yeast strains (the last one I did was North Coast PranQster) and it's worked out well.
"I can't believe how many people think Air Lock is pronounced Hydrometer." -BigKahuna
"If you gave me a beer with placenta in it without telling me I would kick you in the nuts." -ODaniel
"We be in a big hurry for dope beer with much alcamahol and flavor, quality, balance, and aroma don't matter. We just wantz to be druck, u know?" -Yooper