These cases could easily be detected by atypically styled upper kanji 勲 - Merit.
Comparison with a "typical" inscription for "early" (1888-late 1930s) cases (on the example of 6th class cases).
Comparison with "typical" inscription for "late" (late 1930s- 2003) cases.
Currently known...
3rd class sacred treasure awarded in 1956
case for sacred treasure order
inscription styles of sacred treasure order
japanese awards and decorations
japanese medal
japanese order
japanese order of sacred treasure
sacred treasure order
勲三等瑞宝章
勲六等瑞宝章
瑞宝章
japanese sacred treasure order
japanese sacred treasure order statistics
number of order of the sacred treasure issued
order of the sacred treasure
order of the sacred treasure total number
zuihō-shō
勲一等瑞宝章
勲三等瑞宝章
勲二等瑞宝章
勲五等瑞宝章
勲六等瑞宝章
勲四等瑞宝章
瑞宝章