估计是写给客户的吧，因此翻译得比较客气，修改了细节，大意不变，翻译如下：
I am sorry that our MOQ is 1000 pcs for each spec. 500 pcs order quantity is too small for us to purchase fabrics which generally we do not prepare any inventory of. If you are willing to provide us with your estimated annual usage, we would like to give you a better quote.
Thanks a lot for your understanding and support!
抱歉我们的最小起订量时1000件每个规格，500件的量对我们来说太少了，难以买到面料，而我们通常都不会备面料库存。如果您可以提供贵司的预估年用量，我们愿意报一个更优惠的价格。
非常感谢您的理解与支持！
MOQ = minimum order quantity 最小起订量
Pcs = pieces