They've been cleaned, inside & out.

I could find no size tags or markings.

Comparing them to other similar shoes, they appear to be a woman's 7.5, or a men's 6.

The insoles measure about a little shy of 10" long & 3.25" at the widest part. 

Bottom soles measure 10" long & 3.5" at the widest.

They are a little on the narrow side, not for a wide foot.