Sorry, I don't have one to sell, as I have only just got mine... and what an incredible instrument it is!
There are not many around, but they do get advertised here every now and then.
Im sure you have done your research, but just a couple of thoughts occurred to me from your post...
(I apologise if you've already considered them etc, but just in case...)
id be a bit concerned about the phrase: "i was thinking a piano would be too difficult".
I think its reasonable to say perhaps the initial learning curve may be a bit easier (not much though) - as initially you don't have to learn scales, but to get the most out of the eigenharp it takes as much practice as learning any instrument.
Also do you have experience in music software/midi etc, if not , then bare in mind this has a learning curve too, but for me is also a very enjoyable part of the journey.
Don't get me wrong... I don't want to put you off... it is a fantastic instrument and the potential is enormous, but its good to be realistic about the effort required to learn (as with any instrument)
Also, you may want to consider a Tau - new will be cheaper than a used Alpha, has a few less keys, but this really is unlikely to be a limitation. occasionally used ones come up on here.
If you have any questions, post here or over at google + eigenharp group
https://plus.google.com/communities/113007469663952313892
we try to have a weekly hangout, which is open to anyone, so if you have questions this is a good place to ask and meet owners of all types of eigenharps.
good luck with your search