If you really hunger for that item, next time PO from different supplier...that's the best we can do.

sometimes just need to PO with slightly higher price with a reliable shop to avoid such incident. but sometimes worth taking the risk with a cheaper price and being very lucky in the end

I think.... the best choice would be not to allow them to cancel it. Tell them wait for later batches to come and replace with ur slot, since yours the 1st batch issue it would only be appropriate to provide you from the later batches.

This is fair and this will prevent any seller/shops from taking advantage of the hike in price of Mark7.