I'd be watching/buying as well. The 458 looks to be in pretty good/collectable shape still. I'd be curious to know the serial number range to get a date of manufacture. It looks like the bolt is not jeweled which was common on the later super grades.
Like I said earlier, it could have been made from '59-'63, but it would be nice to have the serial # range. Usually the first 3 digits followed by XXX is all that we need. Something like this: 476xxx
