IMO -- and to offer some unsolicited feedback...
I think you are going to need to bring down the price of the power cords.
If the buyer pays for shipping, your $1.50 cords may be $1.71.
The same quantity, new, from Monoprice -- with shipping to my house is $1.35/ea.
16AWG may also be overkill for some people -- driving LEDs doesn't require the same heavy-duty cabling, and I've seen some people use $1 extensions from the dollar store with their LEs -- with a greater length.