I really like the 37C, and I'm wondering if it is a replica of, a close copy of, or inspired by, a particular vintage razor.
Merkur originally made a different style of slant. If you search the safety razor forum or the BST you can probably find some pictures. They had a thinner handle, which was prone to cracking like the older Gillettes. I believe they were WWII era or earlier, or at least that is what I recall.
The Slant is a 1931 design and has been produced like this since then. That's about as vintage as it gets, imho.
Pomco slant head with my handle design.