The 1963 Proof Franklin Half Dollar was the last Proof coin struck for the series. it is also one of the more common dates in the Proof Franklin Half Dollar series, as it has the second highest mintage. It's mintage is a little over 3 million coins struck. Only the 1962 Proof has a slightly higher mintage of about 3.2 million.
The 1963 Proof Franklin Half Dollar appears to be common all the way up to Grade 68 without non Cameo or Deep Cameo surfaces. There are probably more than 1,000 examples that exist in PR67 Cameo. In PR68 Cameo it is scarce with less than 1,000 examples known. In PR69 Cameo there are less than two dozen known at PCGS with none being graded higher. In PR68 Deep Cameo it also appears to be scarce with less than 1,000 examples known at PCGS. In PR69 Deep Cameo it is the highest grade available with about 2 dozen known.