Shhhh... I'm one of those old Amiga users out there.  I have an Amiga 2000HD which at the moment is dorment.

Let me dig through my archives and see if I have a KickStart image that you can write back to a Floppy Disc.

I can also point you to some Amiga forums if you need to repair the boot sector.

I believe there is a certain forum admin that was previously also an Amiga user, not naming any names. ;)