Is it grammatically correct?
I'm drafting a T&C and would like to check if below is correct or any better way to present this?

$300 Coupons is limited to 100 pieces and available while stocks last.

Question

Is it grammatically correct?
I'm drafting a T&C and would like to check if below is correct or any better way to present this?

$300 Coupons is limited to 100 pieces and available while stocks last.

Answer

The case is that $300 supermarket coupons will be offered to 100 customers who subscribed a specific service. I'd like to express the quota is 100.

Answer

100 pieces of Coupons worth $300, are still available while stocks lasts.

Answer

Is each coupon worth $300?  Can you buy up to 100 items with each coupon?  This is not very clear in this statement.