Who was "Helen Buchanan Seeger"?

The client's mother, Stanley Seeger.

http://greggsmithsingers.com/stravinsky/chrono5.php :

The “Requiem Canticles” was a twelve-tone piece. Its premiere performance was commissioned by Princeton University and Stanley Seeger, in memory of his mother, Helen Buchanan Seeger. She had been a benefactor of Princeton University and especially of the Princeton Music Department.

Thanks Zedef!

You're welcome. If only those times would return when they used to commission work from you...

Zedef wrote:

You're welcome. If only those times would return when they used to commission works from you...

If only the times when there were Stravinskys would return