When you enter the store, ask "Who is the guy in here with the most experience?"

I would carry the alternator into autoparts store, put it on the counter, and ask "can I get another alternator just like this one?"
Can you tell by the part number?
Do you have this alternator in stock?
If he knows what he is doing, he can look up the part number and find it that way.

Otherwise........

Parts guy will ask: "what year"?
ONLY if you have to...........Tell him it's a '95 Honda.
If you mention "Civic" and his screen doesn't list it as stock on a 95 Civic,
parts guy will go crazy, since most parts guys can only look up what was stock.
If the civic did not come stock with a B16A, it won't be in his computer as such
and parts guy won't know what to do.

An experienced parts guy knows different ways to find a part number.
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Open the box, if alternator is dirty or looks like it was installed, go to another store.
Visually look to be sure it is the same alternator.

Whatever they have, TEST it before leaving the store. That way everyone knows it was good.