i have a upvc window which has a top opener. the problem being that my sink unit is in front of the window. and unable to fit the standard fastner as it is too high to open. what i have now is a brass fitting on the sash and the frame and it works as a pulley with a rope hanging down. however the brass has worn now over a period of time and i need to replace it any ideas what this fitting is called or a site which i can buy it from. thanks in advance for any replies