To the OP - you could also consider a simple fermenter box made of insulated foam insulation held together with some duct tape in which to put your fermenter or water bath for the fermenter. It need not be fancy - indeed I know of guys that lager that way all the time. With switching out frozen water bottles, you can lager pretty reliably, especially in a cool basement, if you have access to that.
Then you can use any lager yeast....
If your ambient air is cool enough (maybe not so easy this time of year) I've found it's easier just to put the fermenter in a rubbermaid tub filled with water and add frozen 1 liter ice bottles. I cover it with pink foam insulation, but if you could wrap it with that stuff it would work even better. Low tech, but it works. Better yet would be a cooler that fits a carboy.