with option (1) you could probably get away with keeping the drive-side spokes (since they are higher-tension, they rarely start breaking at the elbow because of fatigue)
with (2) why are you talking about a disc wheel? Is there a reason you'd prefer that over a regular spoked wheel? disc wheels are usually only for rear wheels on time trial bikes, and they don't handle well in wind.

$100-200 sounds about right for a new wheel. And new rim+spokes+wheelbuild will probably run you in the same range.