a couple of carb questions

i recently purchased a 75 kz 400 d. it has a 400 s motor in it according to the numbers.
the motor is running really lean. the plugs are white and it runs much better with the choke on then without. it has keihin carbs on it that im assuming are cvb 36's. the manual says that it comes with a 130 main jet but it has a 125 in it.
my question is. where do you get these jets from? ive searched all over the net. i also went to my local shop and they said they werent available. if these jets are no longer available. could i just drill them out? what does the 125 mean? is that metric?
thanks in advance.

Look at Z1 for parts. They have the rebuild kit for the carbs which come with the jets.

www.z1enterprises.com/detail.aspx?ID=1869

those kits are no longer available.

www.cyclewareables.com/pages/keihin_main...n_main_slow_jets.htm

Scroll down to PRESS-IN MAIN (SECONDARY) FOR KEIHIN

thanks. ive ordered them.