There is a wide selection of radios here, though some are discontinued.
Comments re: 8.33kHz (not MHz)
As for the lens, what planes? Cessnas or A380s?
If your maths is up to scratch you can calculate the viewing angle for an aircraft at a distance.
tan (half view angle) = half length of aircraft/distance.
e.g. B737-800 at 100m, length is 40m -> tan(half angle) = 20/100 = 0.2.
View angle = 22.6deg.
From the wiki page this horizontal view angle is for a lens just above 85mm.
For an A380 at 100m the angle would be 41deg, so a focal length just less than 50mm.
You won't want the aircraft to fill the viewfinder completely so the angle will be a bit bigger and the focal length a bit shorter.
You'll have to check what you can get for a Sony SLR to cover from perhaps 40mm to 200mm. This may mean 2 lenses. Sony bought out Minolta so you should be able to get Minolta Maxxum AF
lenses for your camera or Sony A mount.
There are some 18-200mm lenses for the more recent digital cameras, e.g. Sigma and Tamron but you may need to try them out with a local camera shop to confirm they work with your camera.