The raw capture ends up being around 24gb when compressed to lagarith. The x264 or mpeg2 encode ends up being around 21-22 gb so it's basically like having a raw capture of the laserdisc that can be popped into the blu-ray player.

I understand that you want to preserve quality, but the numbers are confusing you a bit, I think. Just because the lossless AVI is 24GB doesn't mean that you need a similar size after encoding to a delivery format to have something that looks like a raw capture on the disc. After your current encoding is finished, try using a CRF of 16 (which is absolutely sufficient to make something look like the source) and let us know the file-size. I bet it will be something like 3GB.

I won't be resizing or cropping if at all possible.

Wait, so you're leaving it 4:3? I'd strongly advise you to make it 16:9 anamorphic. It won't really hurt the picture, and it will be far nicer for people to play it back without zooming in.