February 7, 2001 snapshot of helm being used from link on Zam.
https://web.archive.org/web/20010207...ng/helmet.html
Found this patch note on Feburary 2, 2001, stating that "more future art was added" via a game file. Perhaps these were the custom helm textures and the Watchman's Helm was the first one to use it? And the custom quests and Tracker Helm were implemented in April?
http://www.tski.co.jp/baldio/patch/20010202.html