The Benjamin Marauder by Crosman. This is a world class PCP (precharged pneumatic) rifle with a 10 round removeable rotary magazine, a fully sound suppressed integral barrel shroud, fully adjustable two-stage trigger, fully tunable valve and hammer. It is regarded as probably the quietest stock PCP rifle on the market. The aftermarket is strong, with the following as an example of what is available: stocks, trigger housings, trigger blades, air tube extensions, and de-pingers, shroud modifications and extensions, bolt upgrades, replacement aftermarket barrels, etc. It is an accurate, very quiet recoilless multishot bolt action rifle, available in .177, .22, and .25 caliber for less than $400. Additional magazines are about $15, versus $80 for some of the European brands.
You need to surf The Yellow Forum. It is the place to learn and connect with anything relating to airguns.
The .22 Benjamin Marauder at Crosman’s website.
Here is an aftermarket CNC machined aluminum stock that uses standard AR-15 shoulder stocks and grips, of which there are many. Very versatile.
And for the future, Crosman’s newest rifle that will be available later this year. The Rogue .357 multishot repeater, a fully shrouded barrel, ELECTRONIC VALVE big bore air rifle. It uses AR-15 pattern stock and grips. Read the LCD display and modify the velocity with the push buttons, no regulator needed. This will be expensive. Expect the ePCP technology to be applied to a .177, .22, or .25 in a few years, or possibly a true semiautomatic action. With the Roque .357 and the Marauder family of rifles and now a Marauder pistol, Crosman has moved upmarket in design and engineering in a big way.
If you are after a single shot break barrel springer, there are many to choose from. Consult the Yellow Forum for suggestions. Be advised, a springer is much louder than the Marauder if neighbors are a concern when you shoot in your back yard.
Modern airguns are made in England, USA, Russia, Germany, Turkey, Sweden, Switzerland, Spain, Korea, and other countries. Powerplants include CO2, PCP, multi-pump pneumatic, single stroke pneumatic, and spring piston/ gas ram. Single shots, multishot repeaters, semiautomatic, fully automatic actions. There are many choices available now compared to what was available when you were a kid.
A used, older 10M competition air rifle might be a good way to go. They are supremely accurate, as in shooting individual house flys off of leaves at 30 to 50 feet without hitting the leaf. 10M rifles are a sublime shooting experience. These were very expensive when new but are affordable now. Supreme engineering and build quality goes into these target rifles. The FWB 300s, Diana 75, and Walther LGR are some fine examples that are available on the used market. All of them have support available by way of airgun smiths who can rebuild and repair them. The Yellow Forum has classifieds where you can purchase used rifles.
Good luck and let us know what you decide!