Your PSU is actually Chinese with a Korean Sticker (see made in China at the bottom). But so is everything made in China. Now the Americans will have to pay extra money for their Electronics, anyway I digress.
If it is going to draw 457 and you have a 500W PSU, I would say that's a little close to the mark, but it does say on the sticker it can do 600W on peak pull, which should be OK.
Remember the GPU doesn't draw max power all the time.
It's a bit of a "yes it will work" but a newer PSU of 550W would be better....
I'd go for it and try the PSU you have now.