I own a 2000 Altima but that is basically a different car from what you
have - they changed the model drastically between your car and mine.
Never had a a problem with its distributor, but have had other cars
that I replaced them on.
Altimas are prone to have a seal fail, causing oil to find its way into
the distributor, from what I hear.

VIN is the "Vehicle Identification Number" - it identifies the car as
an individual.
It is often a hash of manufacturer, model, make, country of MFR and
serial. No VIN number is the same so by your mechanic's thinking no
distributor is alike, which makes no sense:

Distributors are not finely tuned components that are very specifically
made for one very particular car - a distributor, in its simplest form,
just makes sure you have a spark on your plug at the right time.
A manufacturer is not going to make a distributor only for one car (ie
your car, but not your neighbors 94 altima) as that would cost them a
fortune.

They have to be properly installed. Often when people refer to a car's
timing, they refer to the position of this distributor in relation to
the cam shaft. A distributor is physically turned one way or another to
advance or retard the timing. That 'timing' setting is specific to a
car but any distributor can do this for your car.

You can pull a distributor out of another same model 94 altima, install
it properly ("set timing", see above) and it _will_ run. It just has to
match the model of your car. For instance, here is a quick search for
your distributor (assuming a 1994 Altima GLE):

http://replacement.autopartswarehouse.com/parts/autopartswarehouse/wizard.jsp?ye
ar=1994&make=NI&model=ALT-GLE-001&category=All&part=Ignition+Distributor
(Btw, I am not suggesting you buy from that place, it was just a quick
search - there might be cheaper options out there)

Notice that any part query does not care to ask you about your VIN? Try
other searches on other online part stores and you'll find the same
thing.

Seriously, I'd get a second opinion.
Not sure why he's making you believe that this is a very special job
because it really isn't. Distributors do break and need replacing - by
your mechanic's thinking, we'd eventually run out of distributors for
94 altimas which just is not true.
In reality it is maybe 1/2 hour job but a fairly expensive part.

What does your car do, anyway, that it needs a distributor? I take it
that it does not run?

Remco

The VIN is your Vehicle ID #. Often to find parts for a particular model
they need to reference a particular part of the VIN which may identify
where the car was built, when, etc. and that may help the parts guy
decide between two or more possible part numbers.

I had a 94 but never had a distributor problem so I can't comment
specifically on distributors, but I still suspect there is a "failure to
communicate" problem afoot!