Convex, not flat. Much cheaper than repainting your dial, also you'll keep the original one.
Blue Dial for 565 Omega Seamaster Silver Index Convex Dial
Yobokies Fifty Five Fathoms [Modern Blue] Dial for Seiko SKX SNZH | US Seller
Rolex Quickset Ladies DateJust 26 Custom Tiffany Blue Dial For Ref. 69173, 6917
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