Broken metal casement latch and stay - how to fix?

Hi

I have a really old metal window and both the latch and the stay are now broken beyond repair meaning that I can no longer secure the window!

I need a quick easy solution for securing the window.

Because the window is aprx 50y old its seriously rusted and crusted with paint, its difficult to even close it fully, so removing the remaining bits of the old latch and stay and simply replacing them is going to be tricky. There isnt much overlap between the window and the frame and Im hoping to avoid drilling into the metal as i know the drill will slip and i will break the glass!

Any suggestions to secure the window? Do I need to drill and if so any hints on how to stop the drill slipping or the surrounding glass breaking?


Thanks

The problem I have is that there isnt much overlap on the window - see pic.

Dont know how I upload a pic so here is the link to my album (I think??)

//www.diynot.com/network/tan8856/albums/

iirc there could be a thin nut on the back of where the handle was,get a thin spanner and undo,then visit your local scrapyard/reclamation yard and try and find another handle,also if you scrape the paint off of the inside edges and hinge side it may close alot better.