If your VHS or DVD player has an output in the back marked "To TV" or "RF," you can connect that to the TV's antenna terminal through a coaxial cable.
If the player has A/V output (1 video plus 2 audio for stereo), then you can connect those to an RF modulator like this:
http://www.radioshack.com/product/in...95#tabsetBasic
You would then connect the RF modulator's output to the TV's antenna terminals, again using a coaxial cable.
This is how TV collectors watch recorded material on their TVs nowadays, since the USA discontinued analog TV broadcasts several years ago.
You can buy that kind of RF modulator other places; I only gave a Radio Shack link because their stores are found in many cities.
Earlyfilm was talking about a different connector on the TV -- the phonograph input jack. That was designed to use an old-school input. Modern solid-state devices (iPod, you name it) are not designed for that use and might be damaged if you plug them in directly.
It's possible your CRT is weak, but in the photo it is lighting up enough to see, so it should work well enough to get you through the restoration, at least. Perhaps when you're done it will be good enough to watch. The CRT used in these sets is not super-rare, so if you decide you need a better one, you should be able to find one eventually.
Phil Nelson