Yes, there is.Actually the UP! is available in 3 different bezel-types, depending on where they are sold. In other words, there are 3 different bezels available from VW, where one of them is for 1DIN HU.
When I made the 2DIN conversion for my UP! I ordered a 1DIN bezel, so I didn't had to do the mod to the factory radio-bezel, as for this the radio is a part of the bezel itself.
I have the part-number somewhere, for the different 3 types of bezel available, as VW don't even know the options them self, so I had to do a lot of research to find out...