The needle and seat being stuck isn't really a concern, just replace them.
As for the fuel inlet being broken off you may be able to fix it, or have a machine shop fix it. In the past I've been able to drill them out and glue new ones in with an MEK-based contact cement called seal-all.
I used to maintain a fleet of crappy old junk outboards for a sailing program (long story...) and have done this a few times to the 4-stroke mercs that have the stupid plastic fuel fitting on the carbs. Never had one fail in the years of service and abuse these things saw.