I actually have a disk set for King's Quest 6 on a shelf here, gathering dust. It's marked VER#1.0 INT#4.12.93.
9 diskettes plus an update diskette for 9.28.93 Maybe we can work a deal, or I might be able to send a disk image of what you need.
Other games to install? I don't know, I have some old games, mostly in a dead folder on my hard drive. But most really don't work anymore, and I don't know what's complete, so I wouldn't want to promise anything, But the KQ6 set is complete, and original diskettes. Not listed at Sierra software site anymore (except PC version) so should be OK to copy off.