With orders of $25 or more, Amazon offers Beistle Filmstrip Photo Fun Frame 5-Pack for $5.25 $5.38 with free shipping. That's around half the price you'd expect to pay with online party merchants or eBay sellers. The frames measure 12x12".

Note: This item is offered as part of Amazon's "add-on program" and can only be purchased with an order of $25 or more.