Like Jno, I'd use quotation marks, as George Orwell did in this line from 'The Spanish Gypsy' (1868):
[i]'Tis but a mirror, shows one image forth, And leaves the future dark with endless ‘ifs’.[i]
However the OED does recognise the use of 'if' as a noun (which is what Sandy is seeking to do), defining it thus: "The conditional conjunction used as a name for itself; hence, a condition, a supposition." So the use of quotation marks isn't strictly required. However I do agree that the use of an apostrophe is most definitely incorrect.