http://www.howtogeek.com/174705/how-to-reduce-the-size-of-your-winsxs-folder-on-windows-7-or-8/
The WinSXS folder contains all Windows system components. In fact, component files elsewhere in Windows are just links to files contained in the WinSXS folder. The WinSXS folder contains every operating system file.
So, yes, you'll have to reinstall.
(I'm curious how you managed to delete those files. That's a system folder, at least some of them would have been in use, and it would've taken some effort to get them deleted.)