I see, I had thought that one test track was sounding suspiciously good! One more thing then, the NES soundfont I used had about..maybe 30 patches. A LOT of those were like, 'Square Wave 1 - 8' and such (Konami Drums!!), but I think I can assume that they're all...acceptably realistic variations on those 5 voices you mentioned, right? It doesn't really matter, I'm just obsessive Let me try to dig up a link...
....hm, the website has 2 NES .sf2's now..I'll have to check back on my mac at home. Anyway, if you google 'Zophar Soundfonts', its the first one that comes up.