First series episodes

I have been looking steadily for about 2 years now and after reviewing and purchasing several different compilations I have only come up with approximately 2 dozen episodes of the 1951-1959 run. They are often re-issued and re-packaged in various 4, 5, & 10 set packages. The best one I've come upon is a 5 disc set, with 5 episodes per disc, that I picked up for $30.

If anyone has any leads to where I can find some of the other couple of hundred episodes, no matter the media, I would greatly appreciate it.