I hope you can get that much for it. The memory is one of the most valuable parts in the machine. The 128 MB card my 3400 has in it is probably worth more than the machine itself. The power plug in the rear of my machine is practically dead, so I have to hold the adapter in place with scotch tape. I could get $200-250 for my machine as a parts box and probably the same for the RAM card.
Yours, being in good shape, I'd say 500. But check on eBay to see how much they are going for. Sometimes you can be surprised.