Sting Ray Pup
Sold by Conjurer Margoss. These fast and nimble swimmers are highly desired by pet collectors. Though they can appear friendly, their tail stinger can kill on contact. Aquatic type. Pet Journal is wrong and so is the info about Nat Pagle in your garrison selling this item.
The 
Sting Ray Pup is a battle pet vendor from Conjurer Margoss in Dalaran that requires reputation and currency to purchase.
Guide awaiting review
Find Conjurer Margoss
Travel to Dalaran Sewers and locate Conjurer Margoss at 44.6, 62.0. He is a vendor who sells battle pets for Drowned Mana currency.
Purchase Sting Ray Pup
Acquire 
50 Drowned Mana and reach Good Friend reputation with Conjurer Margoss to purchase the Sting Ray Pup. You will need to fish approximately 717 Drowned Mana total to reach the required reputation level and afford the pet.
Tips
Complete Conjurer Margoss's one-time quest to reduce the total Drowned Mana needed to reach Good Friend reputation.
