In mid-1873, the Mint raised(!) the weight of the Dimes and placed arrowheads on either side of the date to identify the new coins. 1873 was a bit of a roller coaster year, with a bunch of different varieties -- some common, some rare, and one unique (the 1873-CC No Arrows Dime). The 1873 No Arrows, Open 3 was one of the more rare varieties of the year. The mintage was only 60,000 coins, thus the 1873 No Arrows, Open 3 Dime is difficult to locate in most grades. Here's the kicker -- the best example known of this date is a single PCGS MS65, one that sold for a record price of $16,675 in 2009. The second best examples, a tiny number of MS64's have appeared on the market for as liitle as $1,300. There are very few cases where any of the top five examples of a particular coin can be purchased at such an affordable price.
Liberty Seated Dime researcher, Gerry Fortin, has identified six different die varieties for this year. All are scarce at a minimum and some are quite rare.