TPMS Sensors - Bulk Buy

The batteries in my tire sensors are most likely all dead. The car is a 2004 V6 and their life span is up. I called Bavarian Export today and they indicated that "someone" associated with the site is arranging a bulk buy for the tire stem sensors at far less than their price of $380 for a set of 4. Can anyone shed light on this? They claimed it was through a company called Precision Frame???
Any help is appreciated as I need to replace them. I am tired of the Flat Tire warning every 5 minutes and all the other warnings relative to a faulty system. Bavarian is out of stock right now but is expecting a shipment next week. Even their prices are far less than the dealer.
Thanks