Broken window coil springs - need replacement springs.
Hello there. This looks like a 15-177 Pivot Shoe, which works with Series 152 Coil Balances. For a spring stamped '8', you'd need the S152-8 8 pound spring. That stamp however is indeed a bit hard to read. To be safe, weigh the window sash that these springs support. Give me that exact weight and I can confirm the spring weights you need.
If your old coil housing is undamaged, you can reuse it; otherwise, see the newer style 15-143, 15-144, and 15-145. These pieces 'sandwich' around each individual coil.
Hey Evangelos. Yes--it's generally best to replace the springs on both sides at the same time--otherwise, the newer spring will wear out faster to compensate for the older, weaker spring, and both parts will break. (2) of the S152-8 8 pounds sounds like what you need. Let us know if you have other questions!
