The Palkia & Dialga Legend (101 / 102) card can be found in the Hs Triumphant set.
Recently sold 13 times and based on those sales is worth around £29.50.
Currently, there are 9 open listings for this card on ebay.
This card sells in the range of £12.87 to £46.13, making it quite volatile.
This Legend card was illustrated by Shinji Higuchi + Sachiko Eba.