At a glance, it looks like the link provided is a cage KIT, not an assembled cage. If you want the door bar to be different, buy the kit and just replace that ONE bar with whatever you want.

And I'll be the one to question using a full roll cage for "safety" on the street. You're putting steel bars much closer to your head than any of the existing interior parts of the car. You're not protecting your head with a helmet. You do the math.

If it's side intrusion you're worried about, remove your door panel and have someone reinforce the INSIDE of your door with additional supports. Cheaper, neater and safer.