How about duplicating it?
Have you thought about making your own piece of faux abalone shell ?
You could use a piece of wood, or you could use epoxy putty to make a mold of the piece, you can add dry powders or bronzing colors to the epoxy, or you can hand color it out.
If you need to, do a search, and use the photos to help you color it out.
If you go with the Faux...
You could use these colors or pattern, or create your own pattern.
If you tell me what colorants you use, i'll try to tell you how to "float" the colors.
Good Luck
Make you own with an epoxy putty stick...
Read my post about "epoxy putty sticks." These sticks are great fillers, they are opaque, so, you can color over them to create the abalone.
These sticks do not shrink, as they contain no solvent, you cut off a piece, knead it until you have only one color, and then you fill the damage, or make a casting, they can be sanded, carved, nailed, screwed, colored and coated, and they cured in one hour or less.
They may have another name over there, so, I attached a photo.