Is there any other rear that will work in my '65 barracuda??????

A B-body 8.75 will work in your car just fine. My Dart was an old drag car, and probably the first thing they did back in '66 was throw the A-body 8.75 out the door. They wanted the bigger bolt pattern for rear 15 inch slicks. I still have THAT rear , and it is only a half inch wider on both sides. Granted, it is a '65 B-body with a 742 case, but the width of the spring perches is only one inch wider. You can just slide the leafs over to make that .5 inch on either side, or just reverse offset shackles. Also putting in a B-body rear will push the tires out closer to the wheel opening lip, which allows you to utilize a wider tire by using more backspacing.
Worried about two different bolt patterns? Don't.