We put Barry mounts on the right engine of our Aztec when we replaced them
about 300 hours ago. They are still holding strong. The Lord mounts on our
left engine will get replaced this winter when the engine gets overhauled.
The only reason we chose Barry over Lord was price. If I remember correctly
I ordered them from www.aircraftsuppliers.com

Have your prop dynamically balanced after your engine install.

Jim