'69 Dart Tail Light Bucket Repair

Need a little help with this one........
Took the original tail light bezels off my 'new' '69 Dart last night and discovered one of the screw mount areas has broken away from the rest of the bucket. Is this repairable? What's the bucket made of? Pot metal? Aluminum?
Will JB Weld work or do I need to replace with new bucket?
Does anybody repop these?
Help!