Rand,
If you like the idea of a pump carbine in .357, you might want to check out the IMI Timberwolf. Here's a site:
http://www.remtek.com/arms/imi/
Seems like it might be a fun and versatile gun, and I believe IMI has a good reputation for quality arms, no?
Honestly, though, I have no idea about it's availability or price.
Mark