I 140 approved, leave job, go back to India - Can keep priority date if return to US in future?

I have an approved I-140 and planning to leave my job.
I will be going out of the U.S. and back to India for the time being.

is it possible to re-use the same I-140 and get the same priority date if I return to the U.S. in near future?

Yes, you can re-use the priority date whenever you return to US in near future.
Your new employer would need to file your PERM again at that time and can use your old I-140 to port your priority date.