The odds for pulling a Serialized card from a random booster pack is generally advertised as less than 1%. Its difficult to find out more than that for your average set, but for the LotR set, we were given a little more information
Index numbers range from 001 to 151
If anything, the PSA 10 premium for these cards will continue to compress as more copies are graded
It's tough to pin down exactly why these cards are coming down in price (though we'd argue restocks are having an influence), and it's even tougher to predict whether they'll stay at low prices
This scene was considered acceptable in the original Japanese context
Another example is the holographic First Edition Charizard from the Base Set, one of the most iconic and valuable cards, which has fetched prices upwards of 200,000 at auction