E PLURIBUS UNUM is a good spot to check for doubling. The dot to the left of E has a considerable shift to it and M shows doubling in different directions. I can't find any reference to type 1 proofs other than 1956 in the PCGS pops (nor ANACS ).
I was just looking through a roll of junk halves and found this 1958 Type II Franklin. In that condition, I wonder if it has any particular premium?
Nice find! I would hang onto it. I think the 1958 Type IIs are much less plentiful than the 1959s. I do not know anyone who has the 1958 Type II in any quantity. Keep in mind that this is a relatively low mintage year anyway (1958 P Franklin = 4,042,000), of with very conservative estimates of 20% Type II, that means 808,400 are out there minus any that have been melted. TC