I have a 43 D/D steel cent in mint condition.
I am not an ANACS or PCGI member and don't know if it's worth it just to get 1 coin slabbed.
Any suggestions?
It partly depends upon what grade you think may be assigned to the coin. Example: Most people wouldn't send in a coin in AG-3 for slabbing (extreme rarities excepted). I used to be a dealer for ICG. ICG charged me $15 a coin for grading and slabbing. I used to have a fast formula around here somewhere... New Grade Value > Current Coin Value + Grading Fee. Your mileage may vary.
That is not the same D/D which is worth big bucks. I would not slab it. Plus, when you slab a variety, it costs you even more. That coin is not worth the amount it would cost you to certify it. Nice coin, but not worth the money.