If fzzbck (sp?) ever gets his site back up you can check the list of ascended players, and only those who joined before Dec 2011 would have Yetis. Many (e.g. Lord Bacon-o) have lost / donated / sold theirs in the mean time, thus my guess that the originals are more rare.
Also, recent prices for Yetis are something like 4x higher than SITOBG [beta Pickles], so a reasonable rough guess is 25% of those who ascended had a Yeti.
I was part of that early alpha, and being the young glitchen that I was, accidentally donated my yeti within the first 5 minutes of playing the game. I, however, am sure there were more than 300 glitches at the time.
There were around at least a couple thousand alpha accounts, and there were some bugs with the 2010 Yeti in which some people got more than one Yeti so there may actually be more 2010 Yeti's than the Imported Yeti.
I personally think the old yeti is 'commoner' in number. We have no exact number, the public, us. I'm guessing about a thousand yetis are out there, though many are on inactive accounts. Many people have lost theirs over time too.
It's just that, it's worth more (10mil+ as people are paying) because it's more wanted. People think of it as the best item ever, and all the propaganda has raised its value. And not many people are selling.
I'm sure later on, the Rare Yeti will become super pricy too, especially cool numbers like #42.