Fixture Design

In what quantities?
What material?

Need more information to give a useful answer.

This part is easily produced without a fixture btw.

you can easily done machining of this part by making this type of fixture

Use bench vice for machining

Before design fixtures you have to confirm type of CNC router you're using. Then can design the fixtures related to your CNC router table..

From downloaded part as I have no software for opening solid works drawing files. From the part file it is made from 1/4 inch thick material. If these are steel parts (or stainless) laser cutting could be a great option to make many of these, or even a few. With a fiber optic laser this would be a good way to make brass or aluminum parts like this as well. This would be of course, dependent on laser cutting providers being in your area.

https://www.youtube.com/watch?v=pMSyGOoesfM

For making large quantities punching with a progressives punch and die would be worth looking into. Machining parts would be slow. To beat laser cut price would be only with large quantities punched.