Balance Guide?

Looks like you need to replace your Top Sash Guide. It's difficult to say which guide you need without seeing an undamaged version out of the window. But check out our 18-161 to start, as it's been used on Alcan windows before. Remove the other guide from the window and compare the appearance and dimensions to see if it's a match. Let me know what you find.

Perhaps I can be of assistance. There should be a take out clip like our 16-002 in the upper track. You would pop it out on both sides, raise the sash pass it to disengage the balances from the sash. Push the sash on one side and swing out the other side. In short, I don't think it will be different from the typical removal and replacement process for top sash guides. See the video below for details. 

Thanks for getting back to us. This definitely looks like our 18-161. All orders can be placed via the online store. Let us know if you have any other questions.