First of all, spare parts in the market are from many special sources, they are not produced on schedule by any authorized factory. The suppliers in the market get the parts from time to time. So the supply on the market is unstable. Therefore, when one item is out of stock, we could not precisely predict when they can be in stock. Secondly, because the supply is unstable, and the price depends on the supply, so the price is unstable either. However, we have to emphasize that this problem just happen once in a while,if you still have to do business with such a market, which have lower MOQ requirement and better pricing, then this is a problem you have to deal with sometimes.