That leadwood looks to be an excellent choice for fretboards, Pete. And "under the radar" usually just indicates there is no threat of depletion. In other words just the kinds of woods we should be looking for.
We've never used true Ebonies; never had any real desire to do so.
Of the two fretboard/bridge materials we currently use, one has very much the same tone as your leadwood. We call it Brown Ebony, but that's just our name. The species is Caesalpinia libidibia and is shown in the first photo. It starts out as a dark brown, and when cut more or less on the quarter, has a nice subtle darker striping. My IPhone didn't pick it up well, but as you mentioned, once it is oiled it darkens and the striping (which I like personally) is harder to see. I've only seen this wood available on the commercial market once - very briefly several years ago, and that fellow is no longer in the business. It's very similar to most rosewoods in density.
The other we've used since day one, and over the last few years it has now become readily available in the U.S. We knew it by the name Katalo'ox (Aztec), but it's been anglicized to Katalox, or even "Royal Mexican Ebony" in the commercial market. It's not any ebony either; the species is Swartzia cubensis. Again it has rosewood-like properties and far as weight and density. Instead of the colder background hue of the Brown Ebony, this almost has a touch of purple.
We tend to use Katalo'ox paired with warmer body woods and Brown Ebony with the colder toned bodies. True Ebonies (unless stained black as so many are) tend to have a greyish background. While that can be attractive as well, I've always found the tones of our two materials to be more attractive to me personally; hence the lack of desire for an ebony.
One final thing we've started doing is thermo-curing these woods. It cuts down on the weight (helpful in balance when we do a longneck) darkens the color even a bit more (not much as we don't take it too far), increases stability, makes them even a bit harder, and tends to eliminate fret end protrusion down the road.