OK if they were 2 3/4" straight sides with 14 optic ribs inside 1/8" thick glass with 1/2" thick base they would probably be authentic.
SOURCE:
Sparkling Crystal by Larry R. Paul
published by Railroadiana Collectors Association
other books in this genre:
Teapot Treasury & Related Items by Richard Luckin
RK Publishing of Denver
The Official Guide Railroad Dining Car China by Doug McIntyre
published by Golden Spike Enterprises
Silver at your Service by Dominy & Morgenfruh
flatware patterns book
published by D&M Publishing
Siver Banquet II
dining car silver serving pieces
by Everett L. Maffett
published by Silver Press
Books like these will tell you about what was known to have existed at the time of publication and what to look out for in the area of fakes.