You obviously haven't looked at the ILLusion Kinetics slides, then...
Fits standard Tokyo Marui 1911 spec barrel bushings and outer barrels... and has a round top, despite being made for the Hi-Capa platform.
PS, your IK image thread doesn't work. Don't hotlink from pbase by right-clicking and copying the link. It doesn't work that way. Just use the URL of the page itself, and add /original.jpg to the end of the link.