you can substitute for fixed aftermarket halo headlights for pretty cheap. You save a lot of weight and they don't take up any space below the headlight itself. I bought a set but have yet to install them so I can't offer any opinions. I can't seem to find a link for the ones I bought but never installed.
chaser aero sells the housing only without lights. This would use a Piaa 1100x style x4
bought here:
Headlight Housings | S13 [CL-S13(CF)] - $299.00 : Chaser Aerodynamics, LLC.
The east bear setup is too expensive in my opinion.
I have used both Piaa 1100x and Catz MSX driving lights as headlights before and they did fine.