Does anyone know of any M4 style A5 stocks that the Magpul CTR will fit on the "buffer" tube?

I'd like to put a CTR on my A5 with an M4 kit on it (Ops 416 in the near future), but need to know if anyone has done this successfully without modification, looking for a direct "bolt on".

Also, if this has been done, was it using the CTR commercial version or the CTR milspec?

Thanks again!