[Elecraft] K2 alternative Tuning knob ?

[Mike W]

GM All,
After 2 months of using my K2 I'm getting very sore fingers due to 
the awfull shape of the tuning knob and its sharp edges. I know 
that one of the 'JAP' knobs fits but I don't know which one, or where 
to obtain one in UK.
Any help appreciated
tnks, Mike W, G8NXD