As far as uncirculated/MS coins go, you can just about throw in all of the branch mint issues from 1920-1927 as difficult finds, especially '23-S, '26-S, '24-S. Also, nice unmolested, uncirculated lincolns with good strike minted in Philadelphia between 1946-1954 are tough to find - MS66 generally go $200-$450 depending upon the year.
S-vdb and 14-d are considered keys, but you can always find them as they are so popular - it is more a matter of your budget and how nice you can afford. Always purchase them certified at the highest affordable grade.
S-vdb and 14-d are considered keys, but you can always find them as they are so popular - it is more a matter of your budget and how nice you can afford. Always purchase them certified at the highest affordable grade.


















