Handywoman, the problem with a question like this is that they are worth exactly what someone else is willing to pay for them. The local scrap metal dealermight give you a couple of bucks and someone wanting to do a kitchen with that retro look might be willing to pay a lot.
I'm going to assume that you really wanted to know and are just use the question as a sales advertisement, and I have no problem if you did because there is a lot of interest in these now. There is one factor that you control in this and that is what you are willing to take for them. A potential buyer knows what he is willing to give for them. The way to find common ground is to look for "comparables" at places like eBay, then haggle from there, if you wish.
Keep two other things in mind. I would not give you anything for them because I love wood. Someone that wants them might give you a lot. But if you want a lot more than what anyone you can find is willing to pay, they could sit in your basement for a long time. This could turn out good for you, if you keep them in good condition, don't mind the loss and cost of the space, and prices really do escalate.
The other factor is shipping. Packaging them for shipment so they stand a good chance of arriving safely will be a big cost, perhaps as much as the cabinets are worth. The closer that you can find a buyer, the less that will have to be deducted from the "How much will you give me? How much will you take?" haggling. I get involved is shipping mechanics tool boxes, some of which cost $100 and some of which cost $5,000 or more. We have better luck with freight companies like Roadway than package services like UPS. And you may be able to negotiate with them that if a piece is damaged, it's not just that one piece but part of an almost irreplaceable set. That will cost you accordingly also.