Search data only when needed Harlowe RPG

At least I made my inventory system, but there is a serious issue.
Example: this is a weapon created on a passage "weapons":

(set: $iron_knife to (datamap:
	"Name","Iron Knife",
	"Description","an iron knife",
	"slot","rh",<!-- right hand -->
        <!-- many other data here -->
))

After obtained ingame, and stored inside an array...

(set: $weapons to (a:))

...the player can visit the "inventory" passage to equip the character, delete the item, check its functions, etc. But how can I initiate an item stored only "on demand"? I mean, if I have hundreds of weapons and items, it will cause some impact over my inventory system.

Any idea? If you need more details just ask, thank you.