David, IIRC, going price is about $600/unit but that included ('00) demo, support and "training", i.e. familiarization, seminar for SRT team.
If you are looking to purchase one without a SOT on a 4, then I believe you are out of luck as I have not heard that any Class 2s got any sears on Form 1s before 5/86. I may not have complete information.