I was just curious if any of u out there know a place where to buy weapon mods beside the gun runners because most of the time they don't have what i want. Secondly where can i get a brush gun and/or an anti-material sniper without killing an Ncr ranger or buying them. If i must kill rangers how can i do that without losing ncr rep cause my they Idolize me so i dont wanna lose that.

Thanks whoever might know.

The female gun merchant (the one by the truck on the west side of the overpass) at the 188 Trading Post sells a lot of gun mods, too.

But you can't just get a Brush Gun or Anti-Material Rifle for free without killing someone.

I think it might go by level's. My current characters a level 20 and i wanna say the anti-material rifle and other good stuffs started showing up around level 18 or so. I've never killed anyone to get a standard weapon. Also Primm sells mods, Novac sells mods, the gun runner under the bridge at the 188 sells mods.

The items on NPC's are based on how far in the MQ you are...
Elite rangers with Brush guns / AM guns show up once the MQ splits into the 4 or so main branches ( house / ncr / CL / yes man ).
Level has a small effect on random items I think, but I've found mid - high weapons consistantly in containers at or below level 8, long before you can aquire one following the linear path.
This requires going into areas that pose risks however.

Mods the gun runners have the most, Crimson caravan stock some very nice ones and at least three each time.
The 188 stocks some low level ones on the gun runner providing your gun skill is high enough, but I don't think he gets any mid level or better mods at all.
The arms dealer at the 188, mostly stocks, sniper rifle mods, missile launcher mods, the 14mm smgs ? mods, and sometimes hunting rifles.
The dinky shop has some suprisingly good mods compared to its weapon selection.