Why Strength is gets so much love? QQ "I may have great power but what good it is when I can't catch my enemy? It takes more than Brute Strength to win a Fight" -Goku
Poseidon Spear is a back item and it does give +3 or +4 STR w/o a doubt. But he won't be able to get it because it's a Top Spender Item The only way for him to get it is either by doing Top Spender/Enchanting Event (+10 HP/SP/STR/ARM Gem)
Why not get gemstones of strength? That way you don't need a stat shell item. Milk Bottle is the way.