The 1870 Dime is a common coin, though it is not nearly as plentiful as some of the other large-mintage dates of later years. Nonetheless, it is an affordable date in most grades.
The typical Mint State 1870 Dime is MS63, with MS64 a close second. Gems are available -- for a price - but none are known in MS67.
Gerry Fortin, who specializes in Liberty Seated Dimes, has identified six different die pairs (actually seven, but one [F-102] appears to have been delisted). One die pair is Proof-only, another was used to strike both Proofs and Mint State examples.