Yes, get the rifle fixed.
As for the caliber, yes .243 is suitable for deer. I have taken deer, antelope, and yes (gasp), Elk with it. The rifle is now loaned to a girl next door when she started hunting with her family. In 2 years she has taken all her tags with it ( mule deer, antelope, elk ). Maybe next year she will be big enough to handle the .270 her dad got for her. As with anything else, it comes down to bullet selection and shot placement. We have lots of selection today.
I will second the NEF rifles.
-Bidah