This is a tough one. I Googled and found two another machetes with a close match with your lined horn grip made by a WHJ. Co. I couldn't find that firm's origin, but since horn grips are rate and like yours even rarer was sourced from the same supply chain as WHJ. https://www.warrelics.eu/forum/edged...imited-821453/
A EAA forum post shows British machetes with numbers 22, 24 & 25 stamped on the blade. This may also be a clue. These are vintage items and their grip profiles are close to yours. See posts 2, 9 &10.