Yeah, that looks like about 1958. The stem has been changed, though, and maybe the bars. Could be the bars got bent and they couldn't find the old style bars with the thinner middle section so they had to replace the stem.
Looking at the patina on the decals, I think that's the original paint. You'd usually see places in the corners and behind the accessories where the repainters didn't get it right and I don't see that here. That's sort of a rare color to see on a Raleigh, it seems that it was usually on Rudges but I don't think Raleigh bought Rudge till '59.
Good looking bike. I wonder if it has stainless spokes. Those polish up real nice.