personally, i would hitch up and go get it, but i am
NOT a sane person
unfortunately for most folks, a shaper is too antiquated of a technology to be sexy enough to put in their shops.
i do not subscribe to those thoughts personally.
i find the technology enchanting, if not mesmerizing and hypnotic.
regardless, i would be inclined to offer $300 as you had initially thought and see what they say.
i would expect a retort of $350, if you were to be haggling with an initiated seller.
the machine was made to excellent standards.
the machine is robust and capable of moving large quantities of material, at will.
in other words, i would be proud to have a beast like her in my shop.
the machine appears to be in good shape, less the paint.
you should clean/inspect/lube very well before putting any power to her.
but on the surface, you have a very viable candidate in my opinion.
i wish you good luck, whichever direction you go.