1. The handle should fit. I have a Merkur 1904, 33C and razor rock jaws and the razor rock handle works for all of them. Not sure if you can buy just the handle thoguh.
  2. The Merkur 34c is a two piece. My understanding is that you will not be able to use a 3 piece after market handle on it. The 33c is a 3 piece, so handle exchanging is possible.
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