Replacement two different channel balances

The balances you have are likely to be the same style. Although, it is a bit hard to tell based since the attachments on the shorter balance appear to be damaged. The 27" balance can be replaced with either the S380-27 or the S385-27. You'll need to double check the depth of the shoe to confirm the right series.

You can mostly likely use the 26 3 stamp option but it would be advised to confirm the sash weight falls between 13 to 19lbs.

Comparison of the S378, S380 and S385 balance shoes.

The series options are likely to be the same for the 21" balances. If the other balance in that window is undamaged, I would suggest comparing it to that balance.

You'll need to confirm the sash weight to determine the correct stamp option for this balance. There is a chart below the product description of the balances that lists the weight ranges each option can support.