They did/do a remake but with a different design and called the porcupine...
also onza tyres doesn't not have the OnZa logo rights, that's a different company. (It was held by rock and Roll bikes and they 'made' Trials bikes, rings, headsets etc Also held a lot of Magura spare for cheap. Seems to have vanished now though.
Some fun links for reading
Original BikePro info (circa 1995 reviews) of the older no longer sold White Porcupine
http://bikepro.com/products/tires/onza.html and the newer lighter OnZa Porcs II (Racing Porcs) when kevlar came along.
1991 Advert
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I have late 91/(92 season) next to this one in my collection.
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