I don't know what to tell you, it sounds like you've done everything I could think of.
But, there is one on ebay. You could swap the hard drive, or use an Ada to usb adaptor.
https://www.google.com/search?q=Samsung++laptop+300E5C&client=ms-android-americamovil-us&sa=X&biw=360&bih=512&noj=1&tbs=vw:l,ss:53&tbm=shop&srpd=9977091782482382580&prds=num:1,of:1,epd:9977091782482382580&ved=0ahUKEwi99eH2grzTAhWM3YMKHTHTA2sQgjYIsgQ