naturalism

I don't have a good answer. In principle, you should look for an animal that died naturally and take its skin. I once heard that there was someone who does this (I think it was here ), but I heard that his tefillin are quite expensive and quite rare. A friend of mine found a solution by taking tefillin from a deceased grandfather. This is of course not a general solution, but can help with a specific problem. See the video here: https://www.youtube.com/watch?v=Eb6rR_hTZEs See also here:

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And here he suggests dividing and not buying tefillin:

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