I just bought a (.380) 1910 yesterday on my way home from work, paid $300 for it so I guess that's one current data point. Took it to the range today and it's really nice to shoot: goes where you point it (which would mean it hits the target, if I pointed better), trigger feels very good, and there's certainly no question of a FTE - it throws the cases a long way.
I'm not sure about the "considered large" comment - I guess it's large compared to some of the .380 pocket pistols being sold now, but I wouldn't want one of those anyway. It's the same size in all directions as a Walther PPK, and smoother since it's hammerless and has flush recessed sights.
Mine has serial number 514xxx - I Googled a serial number list that indicates this was made in 1965 (though it looks much older, the finish is more brown than blue and has a distinctly prewar look to it). According to this list, your 579xxx serial number would date from 1966.
Here's the list - click on "Mod 1955 380" at the left. The FN 1910 was imported to the USA as the Browning 1955, from 1954 to 1968.
http://www.proofhouse.com/browning/index.html