Thus, the earliest camera listed below is the lowest currently known serial number on a camera with features consistent with a valid five-digit serial number, as noted above. US DesignGustave Fassin. These are relatively rare. Fifth digits are overwhelmingly between one and four. In any case, they are quite difficult to find.
Empirical data suggest range is between roughly and ignoring leading zeros. The range - ignoring leading zeros is per published information.