BBI, Cantrell, GMG are all good options.

 

Another vote for DAS-SPORT here. Been using their products for 20 years. Not everyone had a prominent Penske racing engineer work their designs - but DAS did.

 

Does the DAS bar accommodate being able to move the seat all the way back? I'm 6'0" and have the 18-way GT2 buckets. From DAS's website, the pics look like they've bent/notched the horizontal bar behind the seats back a few inches but I can't tell.

 

@ Seedster,

Based on this post, looks like you can go all the way the back with a GT2 seat.
https://rennlist.com/forums/997-gt2-...-roll-bar.html

I'm running a 996 GT3 seat (fixed back) it can slide all the way back with plenty of clearance. I'm 6'1"

 

@ Seedster, I have a GMG bolt-in Harness Bar for sale that fits all the 997 series that I just took it out of my 2007 GT3. I am 6' 1 and it allowed me to comfortably move the seat all the way back.
https://rennlist.com/forums/market/1276809

 

I had the OEM IVM Clubsport roll bar that bolts to the floor plates and the shock towers. It was a really nice piece with possibly some small measure of rollover protection due to the mounting arrangement. That and the exact German made Heigo copy are both great options if originality and functionality are important. For those wondering, the rear OEM Clubsport bar weighs 39.4lbs which makes it extremely lightweight all things considered because after all, no one likes to add dead weight to the car. Single piece buckets go all the way back with those without any interference. Can't speak for sofa seats.