oem "honda" glass is going to cost probably 3x any replacement "glass" a body shop or glass shop will charge. Their windshields are sometimes 5x+ the cost of others. I'm not aware of any etching/markings on the rear glass towards the bottom, but you can look. Some glass has a faint brand or marking on them. That'd be about the only way someone would be able to tell it wasn't "honda" glass. Again, you can just look at the lower portion of the glass and see if you see any markings.