A
Morris Minor door seal
on a PA-28 would be a "minor" defect.
Austin, or Leyland, or whichever motor car maker made the Morris, did not endure the immense certification cost that Piper did to get the door seal approved. The part might be the same, the certification and tracability certainly are not! Cherokee doors can be fussy, using a non-approved door seal wold not help the situation.
Use the right parts.....
If, on the other hand, you're going to actually fly the Morris, then a Morris door seal would be appropriate!