I thought I'd go out and check my MK1a ... Rick's buffer fits nice and tight. My windshield says 'Pilkington' and was sourced by my local glass shop about 8 years ago . I helped them install it and was relieved that the frame was rust free !
The bad news was that
I had ordered a VB one on sale a couple years before that and had the glass shop store it. I went back there when it was time to install and they pulled it out of that nice foam filled box and it had a crack coming up from the bottom that wasn't on it when I took it there !!! They did some 'fancy footwork' and my old windshield developed an instant crack

( only had wiper scratches before that ) and that turned it into an 'insurance' job which cost me the deductable and they would only order from the insurance company's 'preferred' vendor and the Pilkington one showed up
Not sure if makes a difference but the mirror mount also has the visor mount behind it
...another thing I recall was VB sent me a rubber mount that was just a loop with a channel and totally useless!! Got a proper one from Rick with the molded lower corners and it fit perfect!
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View attachment 18467
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