Quantity and cost:
Right now, with 176 units our per unit cost (without shipping) is around $66.09
At 200 our costs will be around $65.44 per unit
At 250 our costs will be around $63.86 per unit
(this is based on current mouser costs, does not consider backorders, and based on $16 per PCB/Heatsink cost--which may -- most likely be less at this quantity).
The more ordered, the less you all will pay.
Kurt