Ok first one of the list, something like a soviet VSS, which is more a submachinegun, but it fires at a decent range, it fires small subsonic pistol rounds..but Im not very familiar with the weapon.
http://world.guns.ru/sniper/sn20-e.htm

Next idea...

Benelli R1

This weapon I have fired, and can attest, very nice..though its clip capacity is small..maybe of course because this is a video game..it could be tweaked..it looks very unique in a few ways, like for instance the magazine, and the the recoil dampening system, it would be prime candidate I think with a little change up from the crew at RS

If you wanna check it out in action click the link below, it will take you straight to the benelli homepage for the R1

http://www.benelliusa.com/firearms/r1rifle.tpl

Walther WA2000

A good concept, never fired one before, heard from a few friends that have, very nice..little on the inaccurate side at times according to them, which is totally different from what is said about them otherwise, Im not sure but its still a bad ass weapon.

http://world.guns.ru/sniper/sn15-e.htm

Galatz (Galil Sniper)

Israeli made assualt rifle turned support sniper rifle, Seen it in alot of movies and games, never fired one...But im doing this research because I like to research guns, and if I can help the crew at RS with an idea, albeit a personel longing...or just something I'd like to see more often..there is always that shot in the dark chance that it may get a second look and a lightbulb may turn on in someones head

http://world.guns.ru/sniper/sn32-e.htm

{Following excert taken from world.guns.Ru.com}

SVU and SVU-A (Snaiperskaya Vintovka Ukorochennaya - Avtomat = Short Sniper Rifle - Automatic) is, basically, a shortened variant of famous SVD rifle, re-stocked into bull-pup configuration, with added folding ajustable bipods and muzzle device (flash hider and noise decreaser). SVU-A is SVU with added full-auto capability.
SVU is intended as a special law enforcement and tactical rifle, and is widely used by Russian Internal Affair Ministry Forces and OMON (kind of Russian S.W.A.T.) in Chechnya. This rifle is more compact, and have somewhat shorter effective range, than SVD.

http://world.guns.ru/sniper/sn19-e.htm

And the final one...for now...

and as was mention before in another thread, which I second..and am adding to the list, an m14 variant..Just because I have a mini 14 and am inheriting an m21 that was custom made out of a standard m14,same field setup and everything just like an actual military version...not too hard to come by..but the M21 ladies and gentlemen

http://world.guns.ru/sniper/sn09-e.htm

(links from Benelliusa.com,and World.Guns.ru)

Im actually also gonna do a concept of something I have in my head..futuristic looking but still might make a badass semi auto sniper rifle...

nice simple weapons.. good ol' bullet firing variants.. gotta love em'

Always good kinds of guns...

They should be pretty quick to make, methinks. The only time consuming part would be the sounds meshes and textures, right?

not much coding here.. a whole lotta simple weapons.

Yep. That looks like some coding even I can do. *hint*

u mean even i can do

Well, I thought it was worth a try.

I would like to see a player automatiaclly camo-flauged, when croutching with a sniper rifle.

in our future plans, camo will play a role