I removed the wobble pump from my S1 and installed an electric pump. I have been offered 350 for it but have no idea what it's worth. I put 500 only because the forum requires an amount. I don't want to rip off a BPF member , but also would like to be educated before making a decision. Also to be up front, I don't like the thought of pumping it while trying to fly the plane in the unlikely event of a quiet engine, that's why I went electric, so any buyer should consider that. Any thoughts?