get Standard Cost Price Item Based on Activation date and InventSiteId

public static Price TIDgetSTDCostItemPrice(ItemId _itemId,TransDate _activationDate,InventSiteId _inventSiteId)
{
    InventDim       InventDimLoc;
    InventItemPrice inventItemPriceLoc;
    
    InventDimLoc.clear();
    InventDimLoc.InventSiteId = _inventSiteId;
    InventDimLoc = InventDim::findOrCreate(InventDimLoc);
    
    inventItemPriceLoc = InventItemPrice::findCurrent(_itemId,CostingVersionPriceType::Cost,InventDimLoc.inventDimId,
                                                      _activationDate,_inventSiteId,InventItemCostingType::Standard);
    
    return inventItemPriceLoc.Price;
}