If there is no limit listed, then you are fine.
From the Guide:
Every item that you find on a chronicle sheet is
considered always available for purchase for you, regardless if
it’s on your first chronicle sheet or your 21st chronicle sheet.
The exception here is items that have a purchase limit. You
may never purchase more of that item throughout the life
of your character than what’s listed as the purchase limit.
A GM must be present in order for you to purchase items,
so you may only purchase items during or after a scenario.