FWIW, I advertised my (good condition) 5ME with autobox for $400, looking for a quick sale. I was litterally overwhelmed by the number of people calling (most intimating that they regarded that as a 'bargain price'!). An engine affectionately known as The Boat Anchor. Go figure.
That whorey old addage 'its worth what the biggest sucker is willing to pay' is probably quite apt here.