DuraECO via Amazon offers Amazon Prime members this HP CB435A Compatible Toner Cartridge for $9.94 with free shipping. (Non-members can spend over $25 to qualify for free shipping; otherwise, shipping costs $6.31.) That's the lowest total price we could find by $6, although we saw it for 45 cents last week (since expired).

Amazon Prime membership is $79 per year; however, Prime is free for college students for six months, and free for parents and caregivers for three months.