I believe JFZ brakes is no longer in business or it was possibly renamed or acquired by another company. Several US brake companies share the same origin so many of the dimensions and specs are the same. Your Wilwood calipers appear to be the older version. I'm sure Wilwood can supply new seals but you will need to determine the piston sizes (diameter and height) for them to help. I suggest changing the seals and pistons. It is also important to verify that the bores are in good condition.
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