Thanks for the replies. I'm investigating getting a replacement WC router spindle but in the short term will most likely have to get the Porter Cable repaired as we a few jobs to get out imminently so any recommendations of even where best to search for an engineer would be great.

Regarding a replacement, I'd be grateful if you'd have a look at the pictures in this link and considering how the current router spindle is attached to the CNC router machine, let me know how I would go about attaching a new router spindle.
http://postimg.cc/gallery/g1673dy2/e0a43030/

Thanks in advance.