It's an Inductor, but as to the value no idea. Hopefully someone more into the PSP stuff will chime in.
They typically have the value printed on the top, like the others on the board there marked 3R3, 4R7, so that AG marking is odd. Could be that's just the code they use and it stands for the value, but you'd have to know the manufacture and get the DataSheet on it to decipher it. The only way to determine what it could be would be to remove a couple of the other ones marked AG and measure them, but you'd need a meter that can measure Inductance for that and have to hope they all measured the same then otherwise that AG marking means jack diddle.
Might be better off looking for a scrap board someplace and using it as a parts donor, at least you'd know it would be the correct component and value then.
If I were going to just toss something in there to try, it would be a 3.3uH, ferrite core, shielded, and that is solely based on other pics of PSP board versions and what seems to be the same power management area of the board. Do not take that as what it should be though, as I'm just shooting form the hip there, and don't just toss a wire in there as a 'fix' either.