I agree with stressfire. I've collected them for decades now. That is one of the later models produced before they changed over to the Stainless SF-VI. Prices generally are about what he said.
There's one in a local gun shop right now priced at $800.00. I have a nickle one & I wouldn't take less than $1,000.00 for it. I carry it occasionally. The longer I keep it the greater the value.