Swietenia macrophylla (Honduran mahogany) and
Swietenia mahogani (Cuban or West Indian mahogany) were both common in commerce at the end of the 19th and the beginning of the 20th centuries, with
S. mahogani being more commonly used. African mahoganies (
Khaya spp
.) were also readily available at that time.
Today, the available
Swietenia mahoganies are generally plantation grown, mostly in Asia. I suspect that plantation-grown mahogany, like most plantation-grown woods, might be less dense than wood cut from trees grown wild in natural forests, the kind of wood available to Morris.
There is considerable natural color variation in mahogany, even in mahogany of the same species and from the same geographic area. Last summer I broke the front seat rail of the bow seat of our 1922 Old Town Ideal -- an AA grade canoe, and so fitted with mahogany seats and other trim. Here is the repaired seat frame (stripped of varnish) with the new rail (the one not cut to proper length and without the hanging holes):
And here it is varnished.
Note that the new front rail is a very good match for the original rear rail (and a good match for the broken rail in the picture above), but note also that the original side rails are much darker in color.
Here it is above the stern seat -- note all the color variations in the seats and gunwales -- some wood is more yellow, some more red, some more brown -- all unstained mahogany. These photos taken in artificial light tend to wash out some of the subtlety of the woods' tones.
I imagine that Morris stained the wood of his canoes (including, I believe, the cedar of the ribs and planks) to foster color uniformity. I think you should not have too much trouble staining to match new wood to old. I think you will probably have more trouble matching density and grain.