No, you will never see such a designation for this season’s fiftieth Super Bowl. Why? The short answer is because the NFL has discontinued using Roman numerals. The longer answer is that they stopped because “L” normally stands for “loser,” and who would wear NFL clothing featuring an “L?” Then, too, few football fans would even know “L” is 50 in Roman numerals, and this would confuse them for another 39 years (to the 90th Super Bowl) when “C” comes up, confusing them all over again. And the girlfriend would never wear a cap with a large “C” for the 100th Super Bowl.
There are websites that will convert any Arabic number from 1 to 4,999 to Roman numerals. Roman numerals only go as high as 4,999 (they had no need for a symbol for 10,000), and zero wasn’t invented yet.
People generally understand Roman numerals up to “XII” because we see them on clock faces, but not many can translate them any further. Movies used to show their production year in Roman numerals, but no longer. Neither are they used on buildings anymore. Only Miss Cook, our Latin teacher, could understand them now, and good riddance, I say.
The general rule for Roman numerals, which you probably never thought about, is that symbols before a larger one are subtracted; all others are added. (Our class year, 1954, is MCMLIV in Roman numerals. The birth year for many of us, 1936, is MCMXXXVI. This year, 2015, is MMXV.)