I just got a Viltrox DC-50 5" External LCD Monitor for my A6300 and it takes the below batteries. Apparently 2 batteries can power the unit for ~5 hours.
They work on other devices as well, see the Amazon title and description for details (link below).
If you have Discover IT and activated this quarter's 5% savings category, you can take another 5% off, making your final total around $17.74 for 2 batteries plus the charger.
Not a huge savings but a good deal if you're in the market for this at the lowest price possible.
DSTE 2x NP-FM500H Battery + DC01 Travel and Car Charger Adapter for Sony Alpha SLT A58 A57 A65 A77 A99 A77V A77II A350 A450 A500 A550 A700 A850 A900 Alpha a99 II CLM-V55 DSLR Camera as NP-FM500 [amazon.com]