Slip On Sandal w/ floral Asian style embroidery. MM/CN/KR Sz 250 US/CA 7.5-8.5?

Slip On Sandal with bright green & fuchsia floral Asian style embroidery. The sole lists 250 as the size. I measured the sole as 9 1/2 inches (please see photos) Conversion charts suggests 250 is a US/CA size 7.5-8.5, but I can not confirm. The sandals have not been used. I slipped them on once to discover the flat foot bed does not support my arch. The flaws - as shown in the photos - could be factory created - on the sole and maybe glue sealing the soul to the fabric along the edge. I suggest inside use, or light walking on patio or deck, they don’t appear to be solid or supportive for long walks or rugged use.