Weathershield Top Sash Balance Replacement

I am trying to replace a top sash balance for a Weathershield Double Hung Tilt Window due to a broken spring. The balance is a beige channel 25" long, 9/16" wide, and 5/8" deep. It has the short S-clip. The stamp is "24" with no other digits or letters. The upper sash weighs 14.2 pounds.

I have attached photos for your reference. Neither of the channel balances that I have found on your website seems to match the color or the guide that receives the sash shaft. I also can't tell from the website photos if your channels have the same cross section as mine. I am assuming that I will need to buy one of your balances and remove the spring for installation into my old channel. Do you agree?

Also, please confirm that should I be ordering the 24R even though my stamp only has "24".

The recommended sash balance was purchased and successfully installed. Replacing the supplied shoe with that salvaged from the original balance worked well. Be aware that this Swisco part is a galvanized finish and not the beige color of the original. Because I was replacing the top sash balances, the color is not visible with the window in the closed position, so it's not a big deal.