yeah... Isopropanyl (sp?) alcohol is essentially rubbing alcohol, though you might have to go to a drug store or something to get pure alcohol.

As far as the tea idea, I don't really think that it would work, but you are more than welcome to try it.

Also, when you are making the tincture you are doing this with pure leaves, right? I wouldn't suggest using extract (20x or whatever) because you won't be able to make very much tincture at all, due to the low substance-to-liquid ratio.