Need 4 coils etched as 7CB and would also like 4 coil housing pivots

You are correct in selecting the 15-087 coil spring housing with pivot cam. The coil spring used with it is our Series 180. Your housing appears to identify the spring strength as having 7 pounds of support. With that in mind, I recommend our S180-7 coil spring. You may want to weigh your sash just to be sure; assuming you use one spring on each side, your sash should be 14 pounds. 

There isn't a left or right for these. They're marked that way by the window manufacturer but it's not really relevant. They'll work for either side interchangeably.