Sell or Hold?

I mentioned a couple of weeks ago to Casey Bloyer that I had a Thurman Munson autograph on a 1976 Baltimore Orioles program. I wondered how much it was worth since Casey used to be in the seedy sports memorabilia business.
His jaw dropped.
"You have a Thurman Munson autograph?"
"Yeah."
"What kind of condition?"
"Perfect condition."
"Holy crap, that is worth about 2-grand."
I thought it might be worth about $50 so I was thrilled Casey said it was worth around $2,000. One reason it is worth so much is because it is rare. The Yankees first team captain since Lou Gehrig died tragically in a plane crash on August 2, 1979. One of the saddest days of my life. He didn't sign many autographs since this was before the big memorabilia craze.
I asked the Caseman to help me sell it and he refused.
"You can't sell that," he pleaded with me.
Here's the story behind the autograph.
My mom, grandpa and me took a trip to Baltimore to see the Yankees face the Orioles on July 26th, 27th and 28th at Memorial Stadium in 1976. We happened to stay in the same hotel as the Yankees, The Lord Baltimore Hotel.
The Yanks, despite having a big lead on the O's in the AL East that season, lost all three games. This is when Baltimore actually had a team.
After the loss on July 26th, I was in the hotel lobby, around midnight, just looking around. I was reading the game program that had Paul Blair on the cover. Great centerfielder and a future Yankee. Anyway, Thurman Munson came walking by on his way towards the elevators. I approached him with trepidation. This was one of my heroes, the Yankees catcher! I was apprehensive and intimidated.
I said, "Hi Thurman, can I please have an autograph?"
He didn't say anything. He took the program and signed his name. Clearly and legibly.
I said thanks and he replied, "You're welcome."
I shook his hand and he disappeared into the elevator. I was thrilled. I put the program in plastic when I got home and it has been in the plastic ever since.
To me, the big memory is just meeting Munson, or as my friends and I used to call him, "Thurm the Germ...poison to the other team." The fact that I have a program with his signature on it is nice but if I can get $2,000 for it well..."
So, question time. Should I sell the program? Should I keep it as Casey says? Or, should I hold onto it for a few more years, let the value appreciated and then sell it for more money as my radio comrade Andy Cornell says? What should I do?