I just bought some JE pistons from redline engineering and I am missing 1 ring set.
how much do they cost?

And I only got 2 bags of locks (4 pieces inside each).

how many piston rings and locks should I have in total?

 

should have 4 piston ring sets(assuming you have 4 pistons)
and 8 locks total.

You cannot get just one ring set btw.

 

how much are rings then?

 

call JE and ask...........

 

JE said you can buy 1 set $25