To address your basic points…..available high quality side by sides are far more common in Uk than USA and very scarce in Canada But….
20 gauge doubles are very scarce in UK, less than 1 in 100. Americans love ‘em and snap them up, probably more of these English 20’s in US now. Prices very high.
English 20’s will usually have fixed chokes and double triggers, splinter forends, mostly straight stocks (70-80%). The higher end ones will usually have ejectors.
Most English 20’s were made with short stocks for ladies or teens. Many have well done stock extensions or have been restocked.
The English 20’s are old. Many are very old. Webley & Scott’s and their proprietary guns for others such as H&H or Churchill were made into the early 1980’s and
that’s about the newest you’ll find. You won’t find choke tubes. Most English 20’s were made before WW2, 80,90,100 years old. Many were made before WW1
and there are even some good looking guns from the 1880’s, 1890’s. OLD. Bear this in mind if you’re considering 3000 - 5000 rounds of range use per year, when
these guns break, as all mechanical things eventually do, parts must be hand made and fitted by a skilled gunsmith, time consuming and very expensive. The
styling changes over the last 140 years were subtle and it takes knowledge and experience to tell the difference. Very few could tell the difference in age between
a 1920 gun and a 1980 gun by a few photos alone. All of these can be great guns but almost all will have 2 1/2” chambers which is not insurmountable for a
field gun but could become an issue for high usage.
Vintage American 20’s like Parkers, Fox’s, LC Smith’s, LeFevres are also scarce, generally of low to medium quality and the Americans luv ‘em. And they drive the prices out of sight. Pick up a Parker VHE and swing it around, then do the same with a Webley & Scott, the difference is like night and day. If you’re a shooter and looking for a lively responsive 20 you’ll quickly make your choice. Higher grade American guns are more attractive but handle the same, are astronomically expensive as a 20 and pretty well non existent in Canada, the few that were here have been sold south into slavery. Modern American doubles are mostly low grade like the Savage/Fox BSE, medium grade like the Browning BSS’s and Ithaca/SKB’s where you can find choke tubes and single triggers but also frequently heavy weight and large clubby stocks and forends like a 2x4 and well finished, well proportioned high end guns like the Winchester M21, RBL, Parker Reproduction.
Frequently overlooked are European guns and the Spanish, Italian and German makers have put many fine 20 gauge side by sides into our hands since WW2. The higher grade Spanish doubles by the best makers are fine guns and under valued, under priced. The problem here is that they also produced a large number of inferior quality guns, these are everywhere and few can tell the quality guns from the rest. German guns are well built, robust, if the styling features suits you there might be a match here. Lots of Italian guns on the market, some 20’s too. They are usually well made attractive fine handling guns, many with the features you’re looking for. Prices for unfamiliar makers are very reasonable but a few of the very best are hand made and the prices will make your eyes water. Familiar brand names like Beretta, Franchi and the lesser known Bernardelli produced many medium and higher grade 20’s that are reasonably priced today and Beretta, Rizzini, FAIR, Fausti and others offer a great choice of styles, grades ( and prices ) in new guns.
If you can really define what you want and fit this within your realistic budget the guns are out there, some are scarcer or more expensive than others. Between gun shows, range visits, friend’s collections, appraising and my own habits I probably examine and handle a hundred or more different side by sides per year for years. I find a Very Good to Excellent English 20 SxS maybe once every 5 years, one needing care and attention maybe once a year. Be realistic, if this is your goal be prepared to wait years, pounce quick and pay top dollar. Look to European guns to scratch the itch while you’re searching. FWIW, I currently know of one mid 1980’s English 20 and one Beretta 20 of the same vintage with most or all of your preferred characteristics for sale commercially in Canada. PM me if you want more info.
J.