I just installed the stance on my car and they are by far the nicest riding coilover that I have experienced to date. The construction is hard to beat given the price and with the inverted mono tube design, the piston is the largest diameter I have ever seen. My friend (who is also my builder) will recommend these and he does not endorse anything lightly. The stance SS+ are just over $1100. I'm sure our vendors will be able to accommodate these. They are pretty common
If you are not concerned about ride quality but more focus on the track and drifting, then I strongly suggest Powered by MAX for the 240. Again they are second to none IMO for quality and they are developed on the track. They are also almost exclusively for the 240 and they look great to. Not so sure that any of our vendors will be able to get these though. I have only ever seen these for sale by Powered By MAX mostly because they are pretty exclusive.
These are their competition series... $1000
And these are their Pro series... $1350