About M4300-12X12F

Hello, 

I have two M4300-12X12F that due to space issues I had to place in my rack in different Us. 

Now I have the space to place both of them in the same U, but I have lost the bracket that can join them in the middle. Is it a way to get a spare of those brackets?

In negative case,  how can I get them in the same U? with a rack tray?  

Thanks