This is the sight I chose for my .69 English-style muzzleloader, I used only the top-piece, as the base for round barrels wasn't needed.
: Were I to build a DGR, I'd probably use this one, or a similar sight with fewer blades. This one comes in the white, and must be filed-in. I put the silver lines on the leaves.
: As I said, this sight has a base for round barrels which wsan't used on the Octagonal barrel.(of course)
; This sight is available from Brownell's.
: A .375 probably doens't need all these leaves, though. They have others that should be visible on the web site.
: Upon checking the link provided above, my sight is one and the same as the 3 folding leaf sight. Brownells price is around $98.00 for the blank + the base which adds another bit of change.