@cluckdaddy76 yes, I do think it is a ko-kinko that has been repurposed a few times. It was probably "in service" a long time.
The kozuka ana was cut through the design work, implying it happened later.
The nakago ana has been reshaped- expanded, then later filled with copper sekigane. Sekigane 1, 2, possibly 3.
This tsuba probably started out as a tanto tsuba has probably seen several blades of various sizes and shapes over a period of ???
There is a simple honesty to some ko-kinko works that is unintentionally Zen when you think the little fellow has survived how many centuries and seen how much mileage on various blades with various samurai or soldiers. The ratios of metals in the shibuichi are less than perfect, and the designs are simple but often slightly hypnotic. The not quite ideal metal mixes, patinas, and colors create quite a kaleidoscope of works that are quite a beautiful gallery defying the more codified classifications we give most Edo era works.
Note: if you are taking it to a bench jeweler, very few of them are going to have any knowledge of some of the exotic mixes and patina formulas used in Japan. While they pick up books on the Japanese metalwork, very few actually have experience. Consider their opinions as "educated guesses".