I don't know the answer to that, but .....
isn't it interesting that 850 and 1300 seem to be the only GP # that was once an engine capacity size for a classic mini? Well, it is to me, anyway.......
Some other cool ones to have would be: 997, 998, 1100, 1071 and my favorite: 1275. Did I miss any? The company built a lot of 850s and 1300s, back in the bygone days of yore.
Histerically historical, eh? or, historically histerical, whatever .

Never mind me, I get this way sometimes!