Can you do the work yourself? If so, you can probably pick up a good running engine for $150 - $600. You could then spend $0 - $200 for incidentals and preventative maintenance like water pump, rod bearings, belts, hoses, plugs, wires, etc.
You could be back on the road for $150 - $1000, depending on what kind of a deal you get and how much extra work you do.
If you have to take the car to a shop I'd guess $2000 minimum.
As for the 3800 question, the only answer I can give is "more." I'm sure others can give more detailed answers.
Custom roll cage and exhaust fabrication