I searched for the retail prices of the 12 most popular Brand of plastic ball pens in Australia.
The average price is $2.90. Australia uses and discards every year 50 million pens, at a cost of $145 million. All plastic pens should be green, with a replaceable ink filler. An ink filler cost wholesale $ 0.10, retail? $0.30? 50 million ink fillers at $0.30 cost $15 million, a savings of $130 million, every year.
Worldwide 12 billion plastic pens are used and discarded. Governments should promote the use of green pens.