non tilt channel balance

Thank you for reaching out! Either our Series 380 or Series 385 look like the parts you need. You'll have to measure as shown below to determine which one you'll need for your repair. 

I'm just a bit concerned with the sash weight and the stamp on the balance's metal channel. You say the window sash weighs 22 pounds but the 2950 stamp is calibrated for a sash weighing 28 to 32 pounds. This would be too strong if the window weighs only 22 pounds. Has this window ever given you trouble while opening or closing it? If it has, I recommend the 2930 option. A pair of balances with this stamp will support a sash weighing 16 to 23 pounds. But if the window has been operating the whole time without issue, you could just stick with the original 2950 stamp. The decision is ultimately up to you. 

Comparison of the S380 and S385 balance shoes.