Check with pbresource.com
Translite: http://www.pbresource.com/transl.html
Glass Lift channel and surround, GTB-24964: http://www.pbresource.com/Stargate.html
If you're missing the piece of glass as well you can have it cut at a local glass shop. You can find the measurements here, https://www.pinwiki.com/wiki/index.php?title=General#Playfield_Glass_Sizes