For the Acura goto oemacuraparts.com
For the Toyota use the sponsored forum link here to Elmhurst Toyota
As far as the Honda goes yeah try to goto Honda-tech and find a dealer linked with that site for increased discount.
The reason I asked about the vehicle was that every vehicle sold in the 49 states (exc. Cali) has to have their convertor covered by an limited federal mandated 8years/80,000 mile warranty (which ever comes first). So if your cat went south it may be covered. You need to PM me your VIN and mileage if its under 80,000 miles and we might be able to get that covered. I'll have to talk it over with a few guys I know to see what we can get done.