Dave Richards, aka The Strap Tailor made two custom ostrich leg straps for me, his work is excellent.
Both are curved end, XL with custom length each side for correct position of a deployant on my 7 3/4 wrist. One is 22-18 IWC style with full stitch, the other is 21-18 for Zenith EP with minimal stitch.
Dave has an extensive range of standard straps, but can produce any custom strap that you need at the same price point.