Plastic or cotton/wooden tefillin for vegetarians

For those of us who are uncomfortable with induced dying (as opposed to death) and don't like the idea of an animal being slaughtered to make a holy object (although some might say this is the best death the animal could hope for) how about tefiillin made from wood, with parchment made from sisal or hemp, and straps made from some kind of non -animal material. Alternatively how about an old aged home for cows and when an animal naturally hits the bucket so to speak, then its skin is used for the tefillin.