Where can I find tremolo arm for Spectrum GT?

I have Westone electric guitar - Spectrum GT (X185). I'm looking for tremolo arm. where can I find any?

Westones take a 6mm trem bar and you can find them at StewMac, GuitarFetish, and just about everywhere. They're usually referred to as being "import size"

Be aware, though, that the Spectrum X185 has the Precision bridge, which has a bar it shares with Bendmaster FT; this bar has no modern exact equivalent - these are much longer with a different overall shape.
The bar Barry has pointed up will fit, but I made a couple of these bars by welding 2 100mm 6mm bolts together at the threads, cutting off the hex heads, annealing the steel to enable easier bending, and painting them black to finish…

corsair wrote:Be aware, though, that the Spectrum X185 has the Precision bridge, which has a bar it shares with Bendmaster FT; this bar has no modern exact equivalent - these are much longer with a different overall shape.

You can see what Corsair is referring to on our website.
This is my GT: LINK

As you can see, the bar is longer so an off the shelf bar may or may not suit your playing style.

EDIT:
I just checked my post record of this guitar and the bar shown on the website is NOT the original.
It is in fact from StewMac Model 1514-B: LINK

Sorry for the confusion.