Thanks for the suggestion. I have used Grandpa's soap in the past and also liked the tarry smell. I'd assume it smells very close - in a soap one cannot tell much of a difference. If you go ahead and try, please report. (Somehow, I was under the impression that birch tar is restricted also in the US, not just by IFRA, but evidently not).
I'm not sure how good it is for the hands, though. Tar is used for certain skin condition like dermatitis or acne, as for instance in anti-dandruff shampoos.
Incidentally, you probably know that the current Knize Ten soap and shower gel do not smell leathery at all and are quite a let down. However, the Bandit shower gels smells fantastic, very close to the perfume, the butchest leather around (it is not birch tar, however, but some type of isoquinolines, I believe).