Having read on here that heating the pipe up meant that you can replace just the connector, I can confirm this does not work. I have resorted to cutting the old connector off in the hope that there should be enough pipe left, but then found that even with heating the pipe it would not soften sufficiently to allow the new connector to fit.
If you require a replacement connector then only the complete pipe is the solution. I can only presume Ktec sell the connectors for those making their own pipes up from scratch.