RETURNING OF ITEMS AFTER ONE YEAR

Good day! I'm working in a Korean Auto Parts & Engines Importer. I'm now having problems with a customer who issued a post-dated check to us 3 months ago. This morning I called the said customer to his store to inform him(but he was actually aware of it) that the check he issued to us dated on September 30, 2012 is no longer active(closed!). I told him that I want to change the check to another to settle his debts. He said to go to his store on Wednesday so he can change it BUT he wants to return some items he purchased last October 5, 2011 to be deducted from the check that he will change. Obviously, I wouldn't let that. There's no such thing as returning the item after a year right? That's ridiculous. But he told me that if we will not acknowledge his wants then he'll never pay us. What should we do? Please help us!

personally deliver a notice of dishonor to him and you can file a bp 22 case

Thank you Atty.! But is there an alternative to collect the money from him without suing?