Thing is Hurdy it takes 10 minutes to fit and code the new cluster so if you get one for £50 - £100 then your quids in!!
I know its not a new part but thats the chance you take when you buy anything 2nd hand, and yes I have been caught out but I have still ended up paying far less than £420.
To be honest Id never pay £420 for a highline is just not worth that IMO