Please post your answer:
In addition, the shirt should button down the front -- not have a
placket. It should be washable which I didn't think I needed to
mention for a cotton shirt. Finally, most important is LIGHT weight --
it should waft rather than protect from the wind (that's a little
exaggeration but do you get the drift?)

Hello bleublue,

There is a company called Deva, a cottage industry that makes
clothing.  I believe it is in New England  But, on their order page,
they say that they take international orders.  It says “Money Orders
only for International Orders.”
http://www.devalifewear.com/

They have what they call the Schooner Shirt.  It is described as,
`Relaxed styling and cool Tahiti Cloth have made this unisex shirt a
warm weather favorite for almost a decade. With a crisp band collar
and single left breast pocket. Full-cut sleeves and deep side vents
allow freedom of movement. About 31in. Long. W/D*.
http://www.devalifewear.com/Category-Unisex_Shirts.htm?AOLHelp=3f099fe0.3e.71c.1&ServerName=www.devalifewear.com&MasterShipping=%7e

I hope your husband will like this shirt.  I have gotten clothes from
this company and have liked them.  In the future, they may be willing
to modify their pattern to make him exactly what he wants.

I am glad that I could help.
PbA
Google Answers Researcher

Thanks for pointing out Devali wear. Four stars because though you did
not, strictly speaking, answer my question and I am STILL looking for
those banded collar shirts, I did order the baseball style shirt for
my husband. It is a lightweight beautiful fabric and does not have a
collar. He never wears tshirts and the like so this fills the bill for
some occasions. I even like some of the clothes for myself.