I do believe if your Gaiters are for the modern Bonnies. As Speedies, modern Bonnevilles and Americas all share 41 mm forks, my Magic Eight Ball says they will fit. And look great, IMHO.
When I added them to my 2006 Speedmaster I came across a post saying the Triumph ones were the best...So that was what I got...they have lasted for 3+yres...can't say if they are better than after market...
And to answer your question "Bonnie Fork Gaiter Kit"...Yes that is what I have from Triumph.