Star Trek 11

From Author Wars - https://authorwars.com/publications/star-trek-11-316556.html

Overview:

Title: Star Trek 11
Author: James Blish
Year: 1979
ISBN-10: 0727805045
Publisher: Severn House
Pages: 188
Binding: Hardcover
Type: Collection
Title Reference: Star Trek 11
Notes: According to The Whole Science Fiction Data Base No. 3 this is a limited edition of 600 signed & slipcased copies.
Seems to be the only source, no copies for sale anywhere, perhaps planned but not released