Thank you Tom,
in both sources I found 2 part numbers: 67-527 and 67-120. No more comments and similar pictures, which will fit the longstroke !?
I also found that the Amal 276 EU (for the 52 A7) has a right hand float, the 276 CY (for the 48 A7) has a left hand float. Will now look for one of them.
And I was told that the Amal 76 AG is original for a AJS Model 20.
Regards Rudolf