Replacement Anderson balance D9 7P 27 474

A quick learner from Staten Island NY says:
I have older Anderson windows in my home, Narrowline I believe.
I am looking to replace many of the spring sash balances. The number stamped on one of the balance boxes is D9 7P 27 474. That is for a double hung wood window which is double payned. Measurable glass visible is 28 1/4"W x 20"H top sash, 28 1/4"W x 20"H bottom sash. Are your new Anderson balance boxes interchangeable and which ones would I need. (both balance boxes r & L have the name model number.)
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Mike from SWISCO responded:
Thank you for contacting us.

Please take a look at the 24-737 Andersen Replacement Sash Balance.
A quick learner from Staten Island says:
I recently purchased Anderson Narrowline sash control boxes for several of my windows from you and they are working fine. I also need some control boxes for other sizes of windows.
They are double hung, double glazed. I have more of the same type window but different sizes.
3 additional sizes I need:
#1 Top Sash 36 3/8"W X 22"H (all measurements are for exposed glass)
Bot Sash 36 3/8"W X 21 7/8"H
#2 Top Sash 20 3/8"W X 15 7/8"H
Bot Sash 20 3/8"W X 15 7/8"H
#3 Top Sash 36 1/2"W X 15 7/8"H
Bot Sash 36/1/2"W X 15 7/8"H
Which sash control boxes can I use thanks.
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Mike from SWISCO responded:
Can you please give us the number stamped on the balance boxes?
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