Try Marlec for BP Solar.
If no joy, try Phonosolar (35mm). Their UK office near York had some in stock a few months ago. Waxman had 3 in stock recently which they were trying to flog.
ET Solar or possibly CSUN/Caymax may fit the bill. Navitron have a couple of Kinve.
None of these are the perfect dimensions but should look similar from the ground.