Use a crystal shield or a dragon sq shield, both really good, or you could try a rune defender
If it is a shield with good defense against ranged attacks your best bet is: Members: Granite Shield Non Members: Rune Kiteshield
saradomin shield
Antidragon shield
the second floor of runescape has a npc walking around with it talk to him he will hand you one.
Their are shield shops all over Runescape. You should be more specific.In North Falador near the fountain.
An elemental shield is 845 gp.
Use a crystal shield or a dragon sq shield, both really good, or you could try a rune defender
grand exchange
no
The best shield for a non member in stat wise is the Rune Kite shield however if you want rarity the You can go for one with a trim in the colour of the runescape gods.
You just fight him, and have a good amount of food on you. You will need a dragonfire shield. That's about it.
If it is the shield that your gang had you can simply go back and get it. But if it was the other gangs shield you need to get someone to get you it.