Help With 1bbl Carb For 200 Ci

Hi,
I'm trying to help our my aunt and uncle who own a 1965 that she bought new after graduating high school. Their mechanic is telling them that the carb needs to be rebuilt, but that there aren't any kits available, blah blah blah. We think that he just doesn't want to work on older cars. Anyway, here are some numbers from her car:
5F07T76XXXX
65AM2922T6431
From this I can tell that it has a manual trans and a 200ci sixer with a 1bbl carb. They have no interest in modifying this car - they just want to keep an old classic running and fun to drive.

What I need help with:
1. Is there more than one type of 1bbl that could be used?
2. Is there anything tricky about working on these carbs? I've gone through factory 4bbls before - this should be easier, right...?
3. Assuming that it's still the original carb, would there be any harm to the car's value if I exchange it for a rebuilt unit, or should I try to keep the original carb?

Thank you!

RacerJames said:

What are the symptoms? Why does the mechanic say it needs a rebuild? I do recall their being fairly simple.
If the problem is an off idle stumble, and too fast an idle, you might check the throttle shaft. after nearly 50 years, it's probably worn, and could use some bushings.

Click to expand...

All good questions. Unfortunately I haven't been able to drive the car myself. I'll have to call them tonight to get more information. The way the question was posed to me was "Our mechanic says the carb needs rebuilding but they say they can't buy carb kits anymore. Can you look into it and see if what he says about carb kits is true, and possibly help us find a mechanic that can work on older cars?"
From that, and what I've heard here already, I think they have a mechanic isn't comfortable with classic cars. I'm sure I could do the rebuild myself if I didn't live 200 miles away. So all I can really do is try to arm them with more information as they search for a new mechanic.
I really appreciate the help I've gotten here so far, and look forward to anything else that someone might have to add.