Does anybody have an idea what my Setton AS 3300 and TUS 600 might be worth? I'm the original owner and they have not been in service for ~15 years. Physically, they look like new and all knobs and levers work as expected. Last time I used them they were running perfectly. I'm hesitant to power them on because of the age of the capacitors and etc. I have all the original manuals, quality control spec sheets from the factory, advertising literature, sales receipts and etc. These were purchased in 1975.