I'd definitely go for the 301 but I'm a cheapie...not sure I'd go more than $25 w/o a case (or with one for that matter which is why I don't currently own one!). Yes, make sure the bobbin case is there - otherwise a major bargaining chip! So is no case and/or table. Then again, a card table might be stashed in there somewhere - who knows. That might make the deal worthwhile.
I'd also be tempted by the Elna but probably not a model I'd be willing to pay much for. I'm a grasshopper-lover gal (don't own any though). The White - no great shakes from what I can see.