Hi Erik,
Unfortunately I am unaware of any catalog that offers casters in them but I do have a few ideas of what you can do.
Option 1: My first suggestion would be to check out SketchUp to see if there are any casters available there. You can click HERE to be taken to another post where a user explains how to import SketchUp items.
Option 2: You can create your own ‘wheel’ in the program using some of our custom shapes. From the ROOM catalog, you can go to Architectural Elements > Custom Shapes > Floor Custom Shapes. I was able to create a basic caster using these shapes. I have added an image below showing the wheel and I’ve also attached the file in which I created the wheel so you can also check it out and use it if you’d like.
Regards,
Kris