The part you should be looking at on the Sams is actually CR225 (listed under semiconductors). I'm very weak on solid state sets myself. One of the best places to buy parts for TV sets this age is here:
http://www.moyerelectronics.com/
Best to email them letting them know what you need. Now, I used the cross reference for NTE that they link to and it says to use an NTE 526A (confirmed in a book I have). The ECG book/online reference says to use 523. Just last week I was given a box of triplers and it includes an NTE 523 with a little label that says 523A/526A. Got all that?
I'd be happy to send it to you, we can sort out what it might be worth later, once you see if it works. You can send me a PM with your address if interested.