Yes. As I mentioned, the only place I know where to get the sony ICs is off ebay -- but only the surface mount ones, which are a pain in the ass to solder to. (Supposedly you can use razor blades to separate the legs to make it easier, but I've never tried that method) There's a DIP version out there somewhere (i.e. larger package, bigger legs/pins) but I don't know where to acquire it. I know that the encoder was used for a lot of systems like the 1001 model PS1 and certain sega genesis models also.
There's actually a thread about this somewhere out there...I think assembler games maybe? Anyway, I know you said you couldn't do this, but there
is an official sony spec sheet floating around that has the recommended circuit on it, but that will only be useful for you if you can read circuit diagrams (albiet simple ones, so you'd need to know what a capacitor or a resistor looks like for instance).
Little mini prototyping boards are out there for around $1, so potentially you could build a really rad video encoder board for less that $30ish worth of parts if you're enough of a badass.
Pssssst - you're supposed to tell me what encoders use what chips.
I honestly have no idea about what's out there. Only that I have a "craze arcade.com" encoder which uses the AD 725 and is total crap. It's what I use to play MVS (Neo Geo 4 Lyfe), and the reds are set all wrong (and there are no pots to change settings with, even though there could easily be some). Ugh.