Javascript DRY Pattern - function

New to OO, I am making a game and I have this as my initialState :

let initialState = {
  grid : null,
  player : {
    coordinates : null,
    health : 100 ,
    weapon : "Stick",
    expLevel : 1
  },
  enemies : [],
  weapons : [],
  items : []
}

when DOM is loaded, I am able to initialize weapons and items corretly. However, both of these properties share the exact functionality except the object literal that is initialized :

initialState.weapons = placeWeapons(3);
initialState.items = placeItems(2);

where placeWeapons

function placeWeapons(numberofWeapons){
  let weapons = [];
  let availableSpots = [];
  let placementWeapons = []; //list of coordinates that will place weapons
  let grid = initialState.grid;

  //collect whats available of coords that are not taken in initialState.occupiedCoordinates
  grid.forEach( (row, rowIndex) => (
    row.forEach( (cell, colIndex) => {
      if (cell === 1){
        availableSpots.push([rowIndex,colIndex])
      }
    })
  ))

  //lets place the weapons. When placed, it will update initialState.occupiedCoordinates
  while( placementWeapons.length < numberofWeapons ){
    let randCoords = availableSpots[Math.floor(Math.random() * availableSpots.length)];
    if (grid[randCoords[0]][randCoords[1]] === 1){
      placementWeapons.push(randCoords);
      grid[randCoords[0]][randCoords[1]] = 0
    }
  }
  placementWeapons.forEach( coord => {
    let weapon = {
      name : "Weapon Name",
      coords : coord,
      damage : 3
    }
    weapons.push(weapon)
  })
  return weapons;
}

placeItems

function placeItems(numberofItems){
  let items = [];
  let availableSpots = [];
  let placementItems = []; //list of coordinates that will place items
  let grid = initialState.grid;

  //collect whats available of coords that are not taken in initialState.occupiedCoordinates
  grid.forEach( (row, rowIndex) => (
    row.forEach( (cell, colIndex) => {
      if (cell === 1){
        availableSpots.push([rowIndex,colIndex])
      }
    })
  ))

  //lets place the items. When placed, it will update initialState.occupiedCoordinates
  while( placementItems.length < numberofItems ){
    let randCoords = availableSpots[Math.floor(Math.random() * availableSpots.length)];
    if (grid[randCoords[0]][randCoords[1]] === 1){
      placementItems.push(randCoords);
      grid[randCoords[0]][randCoords[1]] = 0
    }
  }
  placementItems.forEach( coord => {
    let item = {
      name : "Item Name",
      coords : coord,
      health : 3
    }
    items.push(item)
  })
  return items;
}

How can I DRY this pattern?