If its $4$ it seems fair. eisbock was 30$ while i think CR was 35-40 so you might have to add to even it out.
You're looking for CR and WC for those 2 bottles? That's probably not going to happen. For just a CR, maybe, as the Eisbock has decent pull. BB4D is a nice beer, but trades more for like another $5-$8 12oz beer like KBS. Not a $30 beer like White Chocolate.
It trades like an 8 dollar beer because that is the price..Its brewery only and that is what they sell it for...Just sayin...