Chances of getting Book of Scale...

[Phinger]

So while killing time on my lunch break i was looking at the pally epic. Sounds to me like the hardest part is going to be acquiring the book of scale. I say this because I've been on this server almost a year and have never been invited to a vox/naggy/other dragon raid or even heard of them being up before someone snipes them. Some poor guy in the ec forums has been trying to buy one for awhile...

I'm sure it's possible to get, but how difficult is it on p99?