Timing Chain Cover

Pulled the radiator out of my Dart last week to have it cleaned and a leak repaired. Since it was out I gave the water pump a check and saw that water had been seeping out of it. Went down to the parts house and got a new pump. While making one last snug down of the bolts I guess I applied too much force on the top bolt. Ended up cracking the top mounting hole on the timing chain cover. The whole upper half of the mount came off.
Now I need to replace the timing chain cover!!
My question is: Will timing chain cover from other size engines fit, or do I have to find a cover for the size engine I have?
Engine in my 1965 Dart GT is a Charger 273.