ご好評につき = due to high popularity, due to its popular reception, due to popular demand, etc.
再入荷致しました = we have restocked the item
If you mention the item in the sentence:
"Due to popular demand, we have restocked [the item]!"
Ex.
"Due to popular demand, we have restocked our Vintage 1986-Style Bomber Jackets (Black Only)!"
"Due to popular demand, we have restocked the Cat-Pattern Wallet!"
If you don't mention the item and just want to use the sentence as a header or article title:
"Back by popular demand!"