White cast Door pull handle

Each handle is cast or white metal and about 8.25 inches in length. Each handle has 3 holes in it, one for the lock assembly and two for fastening. Our building has these handles on every sliding glass door, each apartment has anywhere from 2 to 8 sliding glass doors. I'm the property Manager and I have 143 apartments, that is a awful lot of door handles.
Our building is 16 years old, I really need to locate these handles. Can you help me?
Thank you
Martin