Advanced Precision Composites (APC, also known as Landing Products Inc.) is the go-to manufacture for high quality model aircraft propellers. Made in the U.S.A. Murphy's law says that you'll always need one more propeller than you've got on hand...so carry spares!
Please select your propeller pitch above. If in doubt, 7 x 5E makes for a great general-purpose 7" prop.
A note about "Pusher" propellers:
Standard propellers rotate counter-clockwise when looking head-on at the airplane from the front, or down onto the top of a rotorcraft. "Pusher" propellers rotate clockwise from these perspectives.
A flying-wing airplane (motor in the rear) does not REQUIRE a "pusher" propeller! Either propeller type can be run.
"Pusher" propeller is a term from fuel engines which are only capable of rotating in one direction. A reverse pitch is required to run a fuel engine in a pusher configuration. Electric motors of course can spin in either direction as determined by the ESC, so "standard" electric propellers can and typically do run in both tractor and pusher configurations. The utility of reverse pitch "pusher" electric propellers comes with multi-motor aircraft. Having a reverse pitch allows a twin, quad etc motor aircraft to run counter-rotating propellers to reduce or eliminate torque roll.