i was wondering if this looked legit looks like it may have been restored his asking 600 for it its in good condition I was just seeing if there is anything off just by in the pics.
Looks like a lot of the bike is added parts. Fenders, seat and wheels aren't 51 Phantom. The other parts might be repop. The bike itself may be a repop. The serial number for a 51 Phantom should be on the bottom bracket and be one of these numbers:
Made May 3rd, 1951 if that was from the bottom bracket. The frame and probably forks are 1951. it may be a repainted frame, or original. The serial number doesn't specify the model, like Phantom, just the year. A look at the chain guard would help, to see if it looks old, or fresh, like a repop.
In 1959, H870xxx was the beginning number. the lookup tool doen't work for Bottom bracket numbers. In 52 they went to dropout numbers.