Searching for RYL-017-1 series 23

I am afraid that code isn't helpful in narrowing down what you need. Can you show me closer pictures of the nylon fittings on both ends of the channel balance? Can you also show me any stamp code on the metal channel? Can you also show me closer pictures of the Top Sash Guide from the front and side? From there we'll do our best to assist you.

Looks like you have either an S351-28 or S390-28. The only difference between these two balances is the depth of the bottom nylon shoe, or the 'heel-to-toe' measurement, so compare both with your old hardware to see what matches best. For a new stamp option choose 2740.