Legally, you have a case for breach of contract and can sue for a specific performance on the contract. Furthermore, if you prevail, you have a good chance of getting the other side compensate you for the costs of the litigation (court filing fees, your attorney's fees, etc.) Practically, however, it will cost you a lot of time and aggravation. And, if the court decides not to award you the costs, you might end up with a* very* expensive box of shells. So, yes, you can make them fill your order - on the original terms. You only have to decide whether it's worth the trouble. If you think that it is, look for a contract litigation attorney. A good one might be able to convince the seller to do the right thing, without going to court.
Answered on May 15th, 2013 at 7:05 AM