I'm pretty sure it's a Kai Gunto, Stainless Steel, genuine Takayamato, Ishihara Masanao kanji, no other markings or stamps or numbers.
Seya, mounts and reddish brown tassel appear to be original and match the era.
He's asking only $700, which makes me wonder, having seen similar signed sword listed for sale for over $2,000.
Thinking of taking the chance and forking over the cash (?)