demby
I'm wondering if you got your rifle, yet? It sounds like you can afford a nice one. But, the challenge is which one?
You say "Prefer break barrel to side or underlever cocking". I don't understand that when you also say "provided barrel realignment is consistent without droop". The answer to that is a fixed barrel!
The best non-breaking break barrel I know of is an Air Arms TX200 which can be had in carbine length. It will put every pellet through the same hole at 25 yards! I know because I own one. This rifle has a fixed barrel, so no drooping to worry about. It does have a beautiful carved walnut stock, though.
If you want quick follow-up shots, the Umarex Synergis has a fixed barrel, uses a magazine and has a synthetic stock which will take the abuse of field carry or (yikes!) being dropped.
However, if you insist on a barrel that actually breaks and uses a magazine, there are a couple of others that I've found consistent enough for pesting:
Gamo Swarm models use magazines and their Whisper technology keeps the report down, especially the Whisper Fusion series. These rifles have been my "truck guns" for several years and have taken a lot of pests. Caveat: avoid any Gen2 models. I had problems with the Gen2 magazines. Gen3 and Gen1 mags work great, though.
Lastly, allow me to recommend a scope for you (in order of cost): Hawke, Tac Vector Optics, SWFA, Optisan Optics, and Blackhound. The things to look for are First Focal Plane (FFP) for your aforementioned parallax, and how close the parallax can be adjusted down to. Most will focus from 15 yards to infinity. Some will come in to 10 yards. Very few will go down to 5 yards. This will be based on your preferences. All of them have good glass and will serve you well.
Before I go, let me put in one more thing about the TX200: none of my many break barrels can out shoot it. NONE.
Good luck and let us know what you finally get,
~ Mondo