Love 'em or hate 'em, Limited Run Games has a reprint of Maniac Mansion for pre-order on NES and PC. The deluxe box even comes with a soundtrack CD. I'm surprised I heard about this when I did but am now extra glad I didn't drop the big bucks on an original CIB copy the other week. I'm gonna guess they're using the original rom, perhaps with some hacking to update copyright credits on the menu or something at most. I'd be beyond surprised if they patched any of the glitches and stuff.

https://limitedrungames.com/search?q=maniac%20mansion