I have a strattas suspenson seat and it has a blow up lumber support inside the cushioning as an extra. it can be fitted to any car seat not just theres . the back of the seat needs to be removed from the base and the bladder inserted up though the middle of the faom . you may have to cut a couple of wire maspro clips to get it inside the back rest but they can be purchased from bunnings in the fencing ilse with the pliers to clip them back
Dont tell stratus your fitting it to a normal car seat lol , tell them you have there seat.
i have fitted two . one in a magna and one in a dunnydore . both took about an hour.
You could try a upholsterer to modify your existing seat into what you want (with side supports/lumber support etc)
Mate had a pretty standard car seats (HQ) which the upholsterer turned into a full race look seats (but comfy) with those sides that really hold you in etc - Dunno what it cost him though but I was very impressed with what the upholsterer did to the existing seats. He also got the seats in 2 colours to match the rest of his car he had been doing up
I had them standard in a Izusu mu recaro /momo pack import 4x4. awsome seats.
but before i lashed out and buy a 2000 dollar seat i would try the 100 dollar air blader insert in the seat thats allready in the car . if it dont work out it can be fitted inside the replacement seat. Just trying to save the man some money . the blader may work .
i totaly agree recaro is beter than stratus in foam and comfort .
Sorry I have no knowledge of after market seats but don't get the standard seat used in $250,000+++ Kenworth trucks lol. Bloody hell they are shocking when a bloke has to have his bum in it for 12 hours a day!!
And towie " & great for holding you in the seat.."