Our billet FE motor mounts are $295. (They come with the purchase of a roller.)
We make them in 2 pieces which makes it much easier to install the motor. Just line up the bolts in the holes and drop in the motor. They are also designed so they can not "break" and have the motor torque over and slam the side pipes into the body...no fun on the original cars. We have a cross bolt going all the way through them to prevent such mishaps.
We use urethane bushings to keep the vibrations down.
David