Hmm... For SID sounds there exists perfect solution called HardSID.
For MSX-Music and MSX-Audio you can use MoonBlaster voice selector that accepts MIDI input.
For SCC there really is no way to play that with MIDI, but I think you should look for MOD/IT/XM or some similar tracker that accepts MIDI input. You can load SCC sample to it, set looping to 0 and there you go...

I'm quite sure the lack of interpolation does it all. For our -delayed- game I'm doing the psg+scc music in Impulse Tracker, in which I can choose to not have interpolation.. and it sounds convincing! I ripped all those typical konami sounds (which I did earlier in SillyCone Christmas) and it gave me instant Konami all the way.