I just hope Kylo Ren keeps his old look. If Disney redesigned him, I'm pretty sure it is for the purpose of making more money from selling episode 8 Kylo Ren merchandise. If they maintain the same old episode 7 design (and people had already bought the toy), then they won't be able to sell the episode 8 variant of Kylo due to the fact that it is the same as the episode 7 variant, and many people already had it. However, I'd like to point out a few things:
1. The mask-Kylo Ren had plenty of time to call in some extra Stormtroopers to get his mask off the bridge. It's gonna cost a lot of money to build a brand new one (especially after the First Order wasted their money on the Starkiller Base). If he does have a spare mask after the first one gets destroyed aboard the Base, it is most likely a copy. Making a copy of the same mask is less costly than making a new one.
2. The tunic he wore-Celebrities and famous people today have hundreds of extra copies of the same clothing in their closet. Darth Vader's mask gets damaged over and over (even that happens in Disney Canon, as seen in the latest Star Wars Rebels episode), and he had plenty of replacements. If he fixed his mask, the effects of the repair would be noticeable (excess screws, bolts, metal covers, and other stuff). We've never seen signs of repair on Darth Vader's mask, so its likely he got a spare one. Back on topic, if Darth Vader can have copies of his valuable helmet, I'm sure Kylo Ren should have copies of his cheaper clothing, ever since Rey damaged his cloth in their duel. If he had health repairs and medical care for his wounds, then his undamaged cloak should cover the injuries, making it look that nothing happened to him.
3. The lightsaber-Like I said in the first two points, he might have a copy. If that is his only one, then he would get a new lightsaber.
