1943 D (RPM?) Lincoln Cent?

I really appreciate all the info, guys! Really, thanks for all your help.

I'm a little reluctant to take it out of the flip because the writing on it was my grandpa's. On one hand, I'm the only person still around who would care—and it will eventually go to my beneficiary who never knew him. OTOH, it's a little something remaining of the man who patiently read the same stories to me over and over until I could tell them from memory, and who put me through college, debt-free, when he didn't have to (he was my mom's stepdad). That makes it a hard choice. Obviously, I'm asking all these questions more to learn about the coins than to determine their value, since the only way I'd even think of selling is if it was that or starve.