If you look carefully, you can find treasures in the Husqvarna shotguns. I have one of the 800 external hammers top lever model 50 circa 1928, I also have a model 20/B i.e. Lefaucheux action (those having a big lever underneath the action), in new, unfired condition. I also have a couple of model 20 16 ga and you can find very interesting combo SxS (Cape Guns) with one barrel being made with either straight rifling (following the same axis as the barrel) or with a pitched (spiral) rifling.
The model deisgnations for the HVA hammerguns are;
M22/22A (1877-80),
the Lefaucheux actionned external hammers shotguns are M/14/14A (1877-82, M/15 (1877-1900), M/15 New Model (1900/1942), M/16 (1877-1889), M/17 (1877-1899), M/17 New Model (1900-1942), M/17A, 17B, 17C (1891-1942), M/18 and M/19 (1877-1891), M/20 Old Model and M/20A (1877-1900 and 1901-1946), M/20B (1944-1956), M/28 (1877-1883), M/29 (1877-1880), M/33 (1877-1880). Some of these models are much rarer than others and as previously specified, the Model 20 is the most common (90 000 made).
There is also the Clef-Serpent actioned (very, very nice and desirable guns) M/38-39 (1879-1891), M/41 (1880-1895), M/43 (1879-1899) and the M/40/41 made on the the Roux action (1879-1883).
The M/31 and 32 (1877-1880), M/34, 35 and 36, M/39 M/40 (1886-1891), made with the "English Underlever" system.
The model 42 (1879-1899), M/44 (1879-1892), M/47 (1884-1899), M/48 and M/49 (1900-1913), M/48A (1901-1913), 48B and 48C (1910-1913), M/50 (1901-1913), M/50 New Model (1927-1934), the M/100 and 101 (1905-1912) all have a similar type of top-lever, back action system (actually, there is two different configurations).
The models 45 (1880-1903), M/46 (1880-1903), M/51 (1911-1947) M/52 (1913-1937), M/52A (1913-1929), 52B and 52C (1913-1938), M/102 (1905-1910), M/103, 103A, B and C, AS BS, CS, AN, BN, CN (1935-1940) all use the Greener type crossbolt system.
Any of these are very good to start a collection. You may have some years of fun to spend there. Some models are heavily engraved, others are quite plain. Some have Walnut stocks, other have beech stock. But all are external hammers.
As for Trade Ex supply of Husqvarna and other Swedish firearms, they are imported from Sweden, following the restrictions the country have set regarding ownership of firearms. A lot of these fine arms are pure bargain, but it won't last forever.