Is it valid add the partner code in url for search page?
Yes, this works, but it provides a little better value if you build a local card database. The product queries return data including a URL that links directly to the specific product you want to query.
Thanks for your answer!
Because a card can have several urls (one for each rarity), I seemed better put a link to search of TcgPlayer and show all rarities of that card.
But I will consider the proposal that you say, thank you!