With orders of $25 or more, Amazon offers The Board Dudes 16" x 20" Aluminum-Framed Magnetic Dry-Erase Calendar
with free shipping
. That's tied with our July mention and the lowest price we could find for any
magnetic dry-erase calendar of at least this size by $4, excluding the below mention. It includes a black dry-erase marker and two magnets.
Note: This item is part of Amazon's "Add-on program" and can only be purchased with an order of $25 or more.
A close price: n.n3288 via eBay
offers it for $6.67 with free shipping.