I broke the passenger side 1/4 slider on my MX Series ARE topper. Suburban Toppers in Denver says ARE discontinued the 1/4 Slider and only makes the 1/2 Slider which means I have to replace the entire passenger side piece of glass at a cost of $130. The slider piece is all I need. Anybody have any sources for used or salvage topper parts thay may be able to help? Web searches have been unsuccessful.