Quite apart from my own lack of any interest in duped items, according to Leurocian, there is one blaze cu per every 23,301 cu sidhes spawned and even that has a chance at rolling as a paragon.
Spawning the blaze cu is actually the easy bit, since getting it tamed and out of the Weald takes a little more doing when every tamer in the Weald leaps on it, interrupts others' tame attempts, and usually manage to kill the poor gaudy thing off thus ensuring no one else gets the prize.
Based on the above only, I'd hazard a guess that there are substantially fewer blaze cu sidhes than there are those duped vine cord sandals.
Thanks, but, well, no thanks.