I bought this Shure SM81-LC in the mid 90's directly from Shure when a friend of mine worked at the company. So, this would indeed be a "vintage" Shure microphone.
It has very few minor blemishes and has see relatively light usage over the years and to me, is in "Excellent" condition.
The foam inside of the box is in tact, but shows signs of aging, as does the black wind screen-- but that can be purchased for about $9 new.
Have a look at the frequency response of this mic, it's about as flat as a pancake, which makes it an excellent choice for a variety of sound sources.
Email any questions and I'll do my best to answer them.