What do you mean by end latches, the 2 pins/rods that slide into those chrome plated things, I can't remember what their call. Or is it those 2 chrome plated things that your looking for. I've got a 78 with t-tops also.
Their are two types of t-tops that were used, one was the Fisher an the other was Hurst. I have the Fisher on my 78, they have a larger glass, the Husrt has a smaller glass. Mine don't have anything that flips up. Mine you slide the glass frame into 2 female chrome brackets, the glass frame has 2 male thingys that goes into those female slots. Then there is a chrome handle on the underside of the frame that when turned pushes 2 locking rods into 2 ( one on each side just above where the window is when rolled up) chrome receivers that are bolted onto the body. I have mail ordered weather striping for the t-tops from NPD an have seen parts for them at Year one & Ricks Camaro, but I believe most of the parts were for Fisher style t-tops. If you have the Hurst style you might check out Fire bird an Trans am parts, I'm not really sure but I think they used more of the Hurst t-tops than Chevy did. I have heard of Hurst style t-tops on Camaros before.
I was just at my other hangout forum, nastyz28.com, if you go their go to body restorations an their is a new post of Husrt style T-tops with pictures an snow. You'll find more info. over there about your t-tops.