Source from aluminum or plastic structure

Does anyone know where you can buy ready made parts like the one I drew up here in this photo. Something in a good stiff plastic or aluminum. This part is about 5" long, but I need a few different lengths of linkage like this. I've seen micrax, and maker beam, but this is more of a lever/rocker arm that I need a couple of them to connect together.

I could make that on a mill, but it would not be very strong. Those square corners in the bottom of the pocket and where the tab protrudes from the end are stress points.

I'd consider some design changes before looking for a supplier.

Thanks. I see what you mean. I'll look into this some more. I could get some 1/2" Aluminum flat stock, and sandwich them together with small bolts.

Servocity has a fantastic collection of very well designed components from Acrobotics and other manufacturers.

Linkages and other motion components here.

One of these might have something useful.

https://traxxas.com/search?keyword=steering