Looking to show replacement
Thanks for reaching out to us! Your T-Lock Shoe appears to be the 15-195 1-1/4" T-Lock Balance Shoe with a closed cam. Be sure to double check that the width of your shoe is 1-1/4" across the bottom of the shoe. We typically see shoes becoming dislodged from the balance when the rivet at the bottom has become damaged. If so, you may want to consider replacing the assembly.
Your balance can likely be replaced with the S795-26 Channel Balance which will come assembled with the 15-195 shoe. Although, given the stamp from your balance, you'll want to double check that the length of your metal channel is 26"; there is a chance it could be 27".
For either balance, you can choose the option ending in C, which will support a sash weighing 17 to 22lbs.
The other detail you'll need to check for is how the balance attaches at the top of the window channel. If screws in, you'll be able to use the replacement balance as is. If it hooks into the top, the replacements may need to be custom made with a hook on top; this will depend on the shape of the installation hole at the top of the window channel.
Please don't hesitate to reach out with any other questions you might have.