There is a new Gas sniper rifle from ARES. Looks good!

PGM338 Sniper,  special features including:
1. Aluminum CNC outer barrel. Simple construction easy to upgrade
2. Folding butt stock
3. Retractable butt stock
4. Adjustable cheek piece 
5. Fully adjustable folding stock & quick release metal bipod
6. Possible to upgrade the power as 600 fps by optional upgrade parts
7.  Specific CO2 magazine is available
8. Advertised Market Price is US$1,200