The first question I would ask will be are your targeted customers actively transact/ respond on ecommerce platform?

Next, do you know the size and whether they are in the same location?

Please be very specific and true to yourself.

If your first answer is no ... then you know the result.
If your second answer is no ... your survival and cost of logistic will kill you.

Another thing - cost effective does not mean profit effective, please becareful.

You should first investigate your strengths in reaching out before searching the appropriate approach to find leads.