Sorry to be the bearer of bad news.
I have just had this issue sorted by a Lexus dealer near me in Essex as I could not put up with the squeak any longer. I am now £1,500 lighter for it!
The clutch is fixed to a fly wheel which are both still under patten, so you can't get from anywhere but a main dealer!
Clutch £863.00 and the fly wheel £925.00!!!!
When the dealer see my eyes popping out in rage they reduced it to £1500.00 which I was still not happy about.
However, my car does not squeak anymore or do I have trouble getting it in reverse anymore.
Hope this helps.