go along to AirsoftAsia and see what they use.
Tokyo Marui is a good reliable bet, even though theyve had their
crown tipped over the last few years by many china[hk] and
taiwanese competitors.
you say you dont want airsoft yet your requirements are way off
both [decent] airsoft and air rifles and air pistols.
anyway, for accurate shooting, within the airsoft range, you could
go for the tokyo marui VSR-10 series of spring powered sniper
rifles [< 1joule ] - low powered but very accurate and would
meet your other requirements if not price [they are the cheapest
out of box best performers - most other sniper rifles would require
some sort of tweaking or ugrading to get the best out of them,
VSR's often perform superbly out of the box].
[for example i had the L96, and spent a few hundred on upgraded
[but swappable] bolts and cylinders to get the performance i wanted
- not exactly cheap for a 'sunday sniper']
compared to air rifles and pistols these are pretty quiet
too.
[and some can come withsuppressors or silencers - certain VSR types
do come in this configuration as well]
do google search and you'll come up with reviews and details.
anyway, the only way to do it legally would be through a
club.
AirsoftAsia would be a start though, even if you just want to go
along and have a look at what they do [competitive IPSC
shooting].
personally i cant stand air pirstols and air rifles - airsoft has
always been a good bridge bewteen the real that you can never have
[in terms of looks and weight, functionality, operation] and safety
[they dont really hurt, have never killed and are far safer than
air rifles and air pistols - and hurt alot less than
painball!]