Does anyone know where I can get hold of window fixings for Boulton & Paul wood framed windows installed around 13-15 years ago? They are a locking cast metal type in a yellowy/champagne lacquer finish. I've got a broken stay and as it's in a room with a lot of other windows, I'm trying to avoid replacing it with a different type as I'll need to relace all the rest too. I ask because Boulton & Paul only appear to want to sell you a new window.