Most locksmiths that deal with uPVC door lock repairs will know that one of the most common uPVC door lock failures is the shattering of the old cast Millenco cams, generally the top follower through continual forcing of the handles. The result is a handle that now spins 360 degrees.
Over the year these have been repaired by swapping the redundant gear with the broken one, anyone that's anyone knows how to do this. I blogged about this a few years ago: https://midlandlocks.angelfire.com/blog/index.blog/1427229/upvc-mech-replacement-parts-locksmith-blog/
The problem now is that once this 'spare' gear breaks we find a mechanism with no useable parts and is a replacement jobby.
They are not the cheapest mechanisms so when someone finally started remanufacturing the gears for the Millenco multi point locks I was eager to get my hands on some - Window Parts Millenco Cams.
Windowparts have had the cams remanufactured to the same spec as the originals and appear to be stronger too. At £10 a pop it is a cheaper alternative to the full Millenco mechanisms which are pricey from some suppliers. Definitely worth grabbing yourself a handful to get you out of a pickle and give the customer a cheaper alternative solution to their broken uPVC door lock.