How do I move a group of nodes to another Drupal instance? What:
I'm breaking a part a huge D7 site into a D7 multi-site instance. 

Why:
Marketing demands have changed. They different units still want to use the same theme but have different main menus and slight CSS tweaks here and there. They also want separate authors and very different approval processes. This site is crippled under it's own weight.  

So far: I've already copied over Content Types via Bundle Copy and most everything that will remain standard via source controlled features.

How/Question: How can I move a piece of content (node/XXX) to another Drupal 7 instance?  A drush solution would be preferred so that I have the ability to script this across Stage and Production servers once we figure it out on Dev.

Errata:
I've seen interesting methods to scrape content via feeds, sharing content, and seen great dev to prod workflows. However, I haven't seen something that addresses a one-time move of a node between instances.
What would suit you is the Deploy module: https://www.drupal.org/project/deploy

The README.txt states:

The Deploy module is used to deploy Drupal content to other Drupal sites or arbitrary systems. Two concrete use cases are:


using it as a content staging solution
using it to push content downstream from a main site to several sub sites.


Here's a demo:
https://www.youtube.com/watch?v=7PjwT0HWHxw