There are plenty of oxblood coloured pipes from the late 19th–early 20th Century, but I’m sure they were coloured before any wax was applied. Sanding the existing wax off of your pipe will probably result in losing any detail in the sepiolite that the carver created. The existing wax will prevent any dye or paint from adhering to the surface.
A less destructive suggestion might be to apply a green wax to the existing pipe. It would require melting several green candles (probably using a double boiler), plugging your pipe with a cork and dipping it in the melted wax; you might be able to use a heat gun to melt any thick spots. I suspect the thin layer will tint the pipe and
not give you the rich, deep green you’re probably envisioning, but it’ll be a little more Cthulhu-like than before.
This is probably a good time to post this previously shared art I did for
Weird Tales Magazine for your amusement that many probably missed the first time around:
