The "right" answer?!?
Perhaps if you could just click, clickey, click and order a .40 Limited barrel...
There's no easy way to get a .40 Limited, so if you're a USPSA shooter I suggest you get the Limited in 9mm, get it all set up, then shoot it as you look for a .40 upper. You can also use the long slide upper from a Match or a Limited Pro; in fact you could probably find a used Match .40, use the upper and throw away the lower for what a Limited .40 upper would cost you