Got some dell E7450s that didn't come with their drive cages. So I just quickly drew up a 3d printable one.

The stock screws if you don't have them are 3x M2.5 x 5mm Phillips screws.

Printed at .2mm with painted supports on the edges of the screw holes, the auto supports just wasted a ton of material but I think they might still work (Check Photos). You will need something to break through the first layer of the screw holes. I made them solid so that it's easier to print and less sketchy when removing the supports. I used a 2.5mm drill bit to break through the single solid layer.

Install instructions: 
Line up the SSD to the ledge of the top screw hole and you should be able to snap the bracket around the SSD. It should fit pretty perfectly in the slot and the holes should be lined up. (Check Photos)

Warning: I only have used it with 2.5" SSDs. I mocked it using a 2.5"HDD so I know it fits but I don't know how stable it is. It still should be fine but I have not tested it.