Only place I know of to get an oil filter for the 5.7 besides dealer is NAPA. Fram also makes one for the 5.7.
fram PH6607 or equivalent
Fram HM3600
Fram C164
the size for a FRAM filter is G7739
The 2008 Toyota Tundra has a V6 engine.
The 2008 Toyota Tundra has a 4.0 L base engine size.
fram ph8a
Fram ph3506
Any place that sells Fram filters will have an application chart that will tell you the correct size filter for your Tahoe.
ph3387a fram
Ph6017a
on my 3.8L, I use FRAM PH16. You'll need to get your engine size to get the right filter.