Need replacement balance springs for Pennco Tilt window

A quick learner from King of Prussia, PA says:
May 15, 2021
I replaced the pivot shoe on my Pennco Tilt window (your video for that was perfect by the way). When reassembling, the string holding the hook from the balance spring broke. I could not fix that. I have photos of the spring assembly and am hoping that you can identify and suggest a replacement. Thank-you
Thumbnail of the uploaded file named Window Spring1.jpg
Thumbnail of the uploaded file named WindowSpring2.jpg
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Paul from SWISCO responded:
May 18, 2021

Hello,

We can make a custom Series 770-28 with a 62-105 hook attached to the cord but we'll need to confirm the spring weight to move forward. Please confirm the stamped code on the metal channel balance. Thank you!
A quick learner from King of Prussia, PA says:
May 19, 2021
Hi Paul,

Thank-you for the reply, the code is "UNIQUE 27-C-30" then there is some difficult to read Code "27 / ???" that I hope you can decipher from the attached photo.

Thanks
Thumbnail of the uploaded file named Spring Weight.jpg
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Paul from SWISCO responded:
May 20, 2021

Your metal balance channel is 28", so you'll need the custom S770-28 with a 62-105 hook. The spring weight for your (27-C-30) stamp will be our (28C) for a sash weighing between 18-23 lbs. We just sent over an order link and price quote for you to review. Take a look and let us know if you need anything else. Thanks for posting! 
A quick learner from King of Prussia, PA says:
May 20, 2021
Thank you for the help, I just placed the order. Appreciate your help
A quick learner from King of Prussia, PA says:
June 4, 2021
The replacement balance spring was a perfect fit. You guys were a great help. Thank you
Pivot Lock Shoe, 9/16" Thick
Pivot Lock Shoe, 9/16" Thick
15-208
$3.57
Heavy Duty Pointed Hook
Heavy Duty Pointed Hook
62-105
$0.74
28" Series 770 Balance
28" Series 770 Balance
S770-28
$12.70
How to remove window pivot shoes
How to remove window pivot shoes
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Anatomy of a tilt window
Anatomy of a tilt window
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How to replace a tilt-window channel balance.
How to replace a tilt-window channel balance.
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Classifying Channel Balance Fittings
Classifying Channel Balance Fittings
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