I haven't measured the Thar windshield but it may be slightly wider than the TJ/YJ/CJ windshield because of the step-out of the tub at the cowl that I pointed out earlier in the thread. I'd be happy to measure one the next time I'm in India, or if anyone knows someone with a Roxor they could measure it - the Roxor windshield would be the same width as the Thar. Even if it were the same width some modification would be needed to the frame - the TJ windshield frame is very different than the Mahindra frames and different from the YJ/CJ frames.
The windshield on the TJ/YJ/CJ is just a flat piece of laminated safety glass and getting a new piece of glass cut to the proper size for a Wrangler can be done at almost any glass shop, so a fairly simple way to do this would be to alter a Mahindra glass channel to fit in the Wrangler window opening and leave the main Wrangler window frame as-is; the new glass in its modified-to-fit the Wrangler channel could be mounted on Mahindra hardware in the stock Wrangler frame.
A few closer views of the Thar window...
On the inside you can see the props that hold the glass open:
Mahindra offered opening windshield on earlier models as well, this is a CJ3b I photographed at the Jodhpur Fort in Rajasthan:
And these are inside views of a military Mahindra CJ3b:
The "hinges" are just pieces of steel that flex when the window opens:
This style of hinges is in very common use today for minivan rear vent windows and extended cab pickup windows but the Mahindra's use of that style predates all of them.
About importing parts to the U.S., that's not hard, you just need to find someone in India who will source the parts and ship them to you.
Another way to add this feature to a Wrangler would be to look to the marine market for parts - all the parts you'd need are available for opening windshield on boats. Bending the channel that frames the glass would probably be the only difficult part but props and hinges for those applications are readily available and could be adapted to the flat Wrangler windshields.
None of the any of above applies to the curved windshield Wranglers (JK and JL).