Vanderkindere, from Belgium, sells on 14 June 2017 a "Dutch School, 17th century" shepherdess, estimated at 5,000 to 7,000 Euro.
The version here is not as good as the original, but still a very high quality version, and could easily be described a "workshop" version (a term which seems to be used for any good, close copy, no matter if the artist actually had a workshop or not). A similar sized comparable work was sold at Christie's in 2015 for 119,000 Euro against a 60,000 Euro estimate, and another one at Christie's Amsterdam in 2008 for 70,000 Euro. A much less attractive "workshop" work was sold at Dorotheum in 2012 for 15,000 Euro, which seems like way too much in that case. Another studio work, quite good but in my opinion not as good sa the one we have here, sold at Christie's Amsterdam in 2011 for 8,750 Euro.
I would value this one at 12,000 to 15,000 Euro as a very good studio copy which lacks the finesse of the best real Moreelse works though.