It looks to me like the mounts are supposed to be encased in rubber, but the rubber is worn off the exterior. The rubber on the interior is still there, but seems to be a little worn.
Would you replace or re-use these?
Rear motor mount - exteriorRear motor mount - interiorDoes anyone else find their bellhousing to be a dirty mess? There was more crud on the bellhousing than the remainder of the engine.