Finally got to the parts , i dont have a spare A5 output shaft but i do have a spare KT 250 one.
Only difference i can see is the thread is smaller and courser and the shaft is solid at the sprocket end not hollow like the KX ones and it is 5mm longer at the thread .
Are you going to CD 6 i can bring it over if you want to look at it .
You may be able to source one locally though .
Would sell this one with the nut $60.00 cheers Bill.