I totally appreciate the nostalgia of playing your old console, but I would suggest simply buying an original NES console. However, I'm not sure if they use the same power supply so I would hate to steer you the wrong way (if the console you were to buy doesn't come with one). But that way you could have your composite out and save the wear and tear on your top loader.
Generally speaking - RF was great when we were kids (we didn't know any better!), but the signal is so terribly piss-poor that you'll soon begin to hate it. I highly, highly recommend doing just about anything to avoid using RF at all in your setup.
If you really want the best there is, get a modder to mod your NES with a NESRGB board -> Framemeister upscaler -> HDMI -> HDTV. Warning: you will need new pants after you see how beautiful it is.