but surely the expression is "to each HIS own", and therefore it’s not a contraction at all.
I can’t think of any way you could contract a word after "each" to make a genuine contraction, nor can I think of an instance of using "each" with a possessive ‘s.
You wouldn’t say, for example, "they each went back to each’s home", you’d say "they each went back to their own home"
"They took each other’s dogs to the beach.", and not "they took each’s dog to the beach.".
I admit I could simply be missing a case where it could be used properly, but I’d have to stand firmly on the side of "each’s" not being a proper construct, either as a contraction or a possessive.
Azh