Based on the pictures I was able to find online that must be 7.5" tall x 5" wide on your 2015 Thor Majestic. Typically when you find a replacement you want to measure the existing cutout to see what would fit.
You might be able to use the Bauer Products Rotary Latch # BA85FR. This requires a 6" tall x 4" wide cutout and has similar dimensions on the face of the latch at 7.9" tall x 5.7" wide. If you have a different cutout size please let me know and I will see if another option is available. view full answer...