A Corsair VX450 (by Seasonic)http://www.hardwaresecrets.com/article/540
or an ANTEC EARTHWATTS 500W (by Seasonic) http://www.hardwaresecrets.com/article/526
would be very good options for you. You will have power enough for a future vga upgrade.
Anyway, if you want to save some money, go for any of these:
OCZ STEALTHXSTREAM 400 (by CWT) http://www.hardwaresecrets.com/article/794
CORSAIR CX400 (by SEASONIC) http://www.hardwaresecrets.com/article/750