Any Duracell Powermat will work to charge the 1520 so long as you have the Incipio case. Best deal is the kits (S3/iPhone). Has a 2 unit charging plate, and backup battery & a phone case. The case is worthless, unless you know someone who needs it, but at $75, its better than the $50 just for the charging plate.
iPhone 4/4S 24-Hour Power System | Duracell Powermat
If you just want the charging base I got this on order should have it Monday.
Amazon.com: Duracell Powermat 1x Powermat for 1 Device (PMA compatible)-Black: Cell Phones & Accessories
I received my Incipio wireless charging case today. I ordered it from AT&T.