That PSU is actually not that bad. Although apparently not made for the US market, it looks like it might have active PFC, indicating a reasonably modern design. Also, FSP units are generally capable of producing what is on their labels. Some of them are "peak rated," and the continuous wattage is typically 50W less, but the image I found of that one's label showed that the 450W is a continuous rating.
Still, it doesn't have the two connectors, and may not have quite enough juice to safely use adapters. I'd suggest replacing it, preferably with something built by Seasonic, (another) FSP, Enermax/LEPA, or Super Flower.