Could on use a pigskin leather bag to keep tefillin in or would it be a bizayon?

Shalom uvracha, It seems that it is not the right thing to use pigskin leather as a tallit/tefillin bag. The pig is mentioned in midrashim as a very impure and dirty animal, and is the symbol of Esav. Therefore, it would be unfit to use it for holy objects as a bag. However, if you have a sack or container made of pigskin (for general use) and you want to put the tefillin bag in it to keep it protected, there's no problem in doing that. All the best