Hi Dan, Back in the mid 1980's I had a Red 507 and I wish I still had that stove !! In December I made the trip to Freddy's and picked up a Green 507 that had been used hard but the price was under $200.
The Jotul burns anthracite very well and it is not dusty at all. We just let the 507 go out on 5-17-2010. The average coal use was about 150-160# a week heating 1,300 sq/ft in the dead of winter. This spring when we shut the Gibraltar down we heated 3,000+ sq/ft with the 507. Stove temp this spring was about 200-250* F for the day time and 400-500* F for the night.
I have located another 507 just 300 yds from our house and they are not looking for much $$$ for it.
For the winter of 2010-2011 we would like to heat the house with 3 Jotuls and sell our Gibraltar DDI.
The 507 will go 12 hours @ 400* F but in the very cold weather it likes 8 hours on a load & shake.
I think they put out about 45,000-50,000 BTU's....