Ah well, it looks pretty basic. You shouldn't need much equipment for that game.
You could ask for a 4850 on oooutlet and an Athlon II x3 with a Gibagyte 970A-UD3 that will allow upgrade, or if that an i3 1210 with a cheap H61 board, it will be more than enough.
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You could buy the rest of the components on Amazon, with the trial Premium they won't charge you shipping costs and they have good prices. You could also go for a Phenom II x4 over 100€, with that graphics card you have much more margin.
I forgot about the power supply, you'd better change it. Playing that I don't think it needs any cucumber so the CX 430 will do, although the 500W one doesn't skyrocket in price. Right now I haven't looked at cheap power supplies on Amazon, I'll take a look and let you know.