Seiko bullhead 6138-0040 came in 2 flavors, the brown “Root beer” and the “Black Horse” with black dial and blue subdials.
It’s a great movement and highly collectible watch. It is very large but fun to wear. Here’s a good overview:
https://www.fratellowatches.com/seiko-watches/tbt-seiko-bullhead-6138-0040/#gref
It came on a fish bone bracelet seen on my black one, and an oyster bracelet on the Root beer pictured. I agree with others that Seiko bracelet you have is fine I wouldn’t change it. It is heirloom might as well wear it as your father did. If you like it and plan to wear it I would find a vintage Seiko friendly watchmaker and have it serviced They are great watches and fun to wear.
Seiko bullhead 6138-0040 came in 2 flavors, the brown “Root beer” and the “Black Horse” with black dial and blue subdials.
It’s a great movement and highly collectible watch. It is very large but fun to wear. Here’s a good overview:
https://www.fratellowatches.com/seiko-watches/tbt-seiko-bullhead-6138-0040/#gref
It came on a fish bone bracelet seen on my black one, and an oyster bracelet on the Root beer pictured. I agree with others that Seiko bracelet you have is fine I wouldn’t change it. It is heirloom might as well wear it as your father did. If you like it and plan to wear it I would find a vintage Seiko friendly watchmaker and have it serviced They are great watches and fun to wear.