Nice work on getting the dial, movement, and hands together without losing any of the white dial printing.
If you haven't found an insert, Milk inserts are gen spec, and personally, I think they are better than the current 1675 offerings from Vietnam. His 1675 cases, bezels, and inserts are all correct dimensions, and can be interchanged with genuine or high quality Vietnamese pieces too.
Here's a picture of one next to a genuine service insert. The genuine service insert is slightly darker with more of a flat, navy blue tone, and the Milk insert is a little brighter. I don't think he was trying to replicate a service insert anyway; it has a red back.