Vintage Heavy Khaki Man's Button Down Worn Work Shirt

Description

Vintage khaki button down work shirt in a very heavy canvas like fabric.  Not sure of the age of this shirt, but I believe it is mid 60s or prior.
The size is unknown.  The sleeve length is 23".  It measures 16" across the shoulders in the front.  The neck is approx 15".  I notice part of the neckline stamp has a 32 on it, so that may also be part of the measurement.
There is a stamp on the inside which reads Baz-Sil.  I suspect this refers to the employee or employees who used the shirt.  (The relative this belonged to had a last name that started with Sil.)
This shirt is very heavy and shows minimal wear in the fabric.  However, there is a light stain on the front pocket, and the back has a line of black stains that spans from arm to arm.  See photo samples. One sleeve has a rust colored stain that is a 2" line.  It is good for theater, films, etc., or someone who will get it dirty anyway.  One button is missing.
I found this in storage while cleaning out a family estate.  I found it folded and packaged, as it would have been returned after dry cleaning.  I un-packaged it to take photos.  So the stains clearly do not come out.  Despite being packaged and dry cleaned, it may have a lingering musty odor from being stored all these years.
This will be shipped in a plastic bag mailer.  I'd be happy to combine shipping. Please ask.