M-Box Limitations/Would Like More Inputs

[Ineedsomeadvice]

Wow, this is my first post! Here goes: I'm currently running my project studio with the older M-Box running Pro Tools 6.9 LE. I'm doing a lot of location stuff and would like more XLR inputs (four is enough) so I can record up to four tracks at once. Digidesign says I can exchange for an Digi 002 Rack/Factory Bundle for $1145 (uuugh). My Pro Tool skills are improving so I don't really want to switch to another software format. Am I stuck buying the Digi Rack or are there other options?
I'm running off of a Mac Powerbook G4.

Any advice would be awesome, thanks! TapeOp Rocks!!