It's very difficult ( maybe impossible ) to find one now. I'd been looking for years & heard one British company makes headers to fit RHD 323i but I've never found it. So I finally bought a Supersprint from BMP. You will need to blend one of its outlet which blocks the way that your steering column goes. Good thing is now you definitely go fast but the trade off is your steering dampner will be killed by heat every year since it's too close to the header plus the header will touch the steering column under hard cornering & makes noise coz' they're too close & engine shifting makes the contact of them. I have also change to use E30 steering dampner coz' it's more easy to replace it. Good luck.