there is this but its kinda expensive. if you dont like the front flap you can try to remove it or take the PMA sticker off and try to put it on your current phone back cover but i wouldnt recommend this

http://www.amazon.com/LG-Official-Quick-Circle-Window/dp/B00LTM37W6/ref=sr_1_fkmr0_3?ie=UTF8&qid=1407525094&sr=8-3-fkmr0&keywords=lg+g3+quick+circle+case+pma

this is the charging mat I use

http://www.amazon.ca/Duracell-Powermat-Devices-compatible-Black/dp/B0082YVBTA