local ItemId = 10541 -- Item needs to have spell on use
local MenuId = 124 -- Unique ID to recognize player gossip menu among others

local function OnGossipHello(event, player, object)
    player:GossipClearMenu()
    player:GossipMenuAddItem(0, "Open Vendor", 1, 1)
    player:GossipSendMenu(1, object, MenuId) -- MenuId required for player gossip
end

local function OnGossipSelect(event, player, object, sender, intid, code, menuid)
    if (intid == 1) then
		player:SetCurrentVendor(90000)
    end
end

RegisterItemGossipEvent(10541, 1, OnGossipHello)
RegisterItemGossipEvent(10541, 2, OnGossipSelect)