360 Modena wiper striking bodywork

All 360 owners, if any of you have a problem wih your wipers catching or as in my case grinding away at the bonnet I have eventually found the reason. The 550 and the 360 have very similar wiper assemblies, only thing is on the 360 the angle where the wiper arm comes of the shaft is basically 90 degrees, on the 550 its slightly less (or more depends on which way you look at it) ie not at right angles, plus there seems to be a more pronounced curve where the hinge is located making it protrude above the bonnet line. My car seems to have been fitted with the 550 assembly and while at Auto Italia this weekend I noticed one or two other 360's with a similar problem. Once I have replaced mine I will provide pictures. I wonder how these items got confused at assembly time.

Also, Anyone know where to source a wiper assembly from as I hear it could be ion the region of £400.