Coldfire Based Embedded SBC's (Score 1)

Cybertec http://www.cybertec.com.au have a product that is based on open-source software that looks like it would fit your requirements.

Processor = Coldfire 5272
Compiler Tools = gnu (linux or windoze hosted)
RTOS = RTEMS (The best RTOS in the world! http://www.rtems.com)

The cost listed on the web site is $ 525 AUD
(i.e. about $260 US).

I have not used the product but I the company is very active is supporting Coldfire and RTEMS.

Best regards
Paul