This 7 inch float has two different maker's marks.

One is on the ID seal.  There's a thick bold clear and complete stamp of WP #17 'Ao' 青 .

On the seal button, there's a lightly stamped version of WP #7-A 'Maru Se' ㊆.

I think it's pretty unusual to find two different stamps on separate seals, especially on an uncommon 7 inch sized float.

Excellent provenance ex-Col. Rich Richardson.

Found in Northern Japan.