You could store the data in a Dictonary like this:
var shop : Dictionary = {
Normal = {
Sword = {
Price = 12,
PicturePath = "res://PathToPicture"
},
Armor = {}
},
Rare = {
Sword = {},
Armor = {}}
}
Within script you could call it like so:
var PriceOfItem : int = shop.Normal .Price
And you get the price of´an Item