RE: Would this work?
The big 3 foot toss around foam gliders often can be found in toy stores.
As for pushrods and stuff you'll want to check out a hobby shop. You need music wire to fit the holes in your servos for starters. Then you need to get the push from the servo to the surface. One way is to use the same length of wire the whole way. But since it is flexible and you can't "push a wet noodle" you would need to use a plastic tube to run the wire in. The tube is secured with glue at each end. With it secured that way the forces trying to buckle the wire balance out and what goes in one end comes out the other end.
There's other options as well since running music wire the whole way is often not a good idea. The options range from plastic tubes in tubes with threaded connectors at each end to traditional folks like me that make my non metal pushrods up from sticks of hard balsa or spruce with wire ends bound to the wood with glue and thread. Others use carbon fiber arrow shafts with wire ends. And there's also flexible cables in supporting tubes that just need stiff wire ends added using solder.
Once you get the push and pull to the control surfaces then you need a Z shaped bend or a quick link to connect to a control horn that is mounted on the control surface. The control horn is what is used to convert the pushrod travel from back and forth to up and down or side to side on the surface.