It seems that the term is used quite loosely. Most that I have seen that are spelled with an H at the end are the usually the actual loofah, but there are lots of loofa toys that have no Loofah in them.
I think most of them that you see are not made from Loofah. They are made from terry cloth or canvas, even latex.
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Apparently the ones on this site are made from Loofah, but there is no picture of theirs.
Buy Loofah Dog Toys, Pet Dog Toy Online – Dig it Pet
If you look at these bone (and heart, slipper, etc.) shaped Loofah dog toys you can see they are made from actual loofah.
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This one has rawhide inside!
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