U B 23 A channel balance, I think length from screw to bottom of channel is 23", with cord & clip extending down the length of the window.

Need to replace small windows channel balance. Upper window will not stay up on its own.No parts removed, yet.  Just scoping out the problem firsthoping it's replaceable.  If this works,  I need several of the same. 
Markings on channel balance: U B 23AFrom product tag on underside of inside upper pane:460  335-912-130T-?8CL