Top sash guide.

Before we can confirm that the 18-174 top sash guide is a good replacement, we would need to see the balance fittings (both the top and bottom) in order to determine the channel series you're using. Many different series balance are used with this particular sash guide. 

Thanks for the additional photos. Your balance looks very close to our Series 395 channel balance which includes the 19-005 top balance shoe and 15-001 bottom balance shoe attached. Please confirm this is the balance for you. If it is, then our S395-28 channel balance with a 2730 option.