Newegg offers the Adata 64GB UV150 USB 3.0 Flash Drive for $7.49 with free shipping. That's a buck below our January mention and is the lowest price we've seen for any 64GB USB 3.0 flash drive. (It's the best deal we could find now by $10.) It features a snap-on cap. Deal ends March 6.
Frugal isn't smart if you put off replacing these things. Waiting too long can cost money or even endanger your health.