Where is the force armlet?

can anyone tell me where is it in order to get shooting star weapon?

Take your pick:

1) Buy at the Esthar pet store.

2) Dropped by Ochu and Malboro.

3) Refine 10 Mag-J Scrolls.

You'll need Tonberry's Familiar ability if you want to buy it from Esthar.

Buying it is the easiest route.