....after looking online we can find the Yamaha part numbers. What I did then was going to Buriram town to the main Yamaha dealer... after being told that they did not have spares for this bike (WR450F) I politely asked for checking again... this time showing the part numbers and asking if they could check once more in they computer (linked to Bangkok I Guess)... and surely... yes we have spares.... seems like the default answer is "no we do not have" when a farang comes in and ask for something that is not mainstream... :-)