Best 150 yard rifle?? Your opinions

Marauder is no 150 yard gun, at least not stock. I own several Daystate rifles that are good 150 yards. My Wolverine .22 HP 60 fpe is very accurate with slugs out to 150 yards and I have already taken a coyote with this gun, although only around 60 yards but dropped him straight down.

My Cricket .25 tuned to 60+ fpe is good to 150 yards shooting slugs and neither of these guns use a lot of air and more than enough power for what you are shooting. Daystate Air Rangers have lots of power and shoot slugs very accurately.

In my opinion, is you want to go long range you need shoot slugs for better trajectory and bucking the wind. Pellets will go that far but not with the same accuracy - or fpe down range if it is needed.

If you are going to shoot pellets then a larger caliber, heavy pellet will be best for long range.
 
I've not been there, but I don't think you'll be getting any 150 yard iguana shots. 

I would tend to believe that with a head shot, anything above 6 FPE on target would do the job. 

You said you want something accurate @ 150, but don't need a lot of power, you just want to buck the wind. But it's power in the form of a heavy, aerodynamic bullet, (as opposed to an un-aerodynamic diabolo pellet) that bucks the wind best. Tofazfu has a few videos on YouTube of him going for 200 yard kills on ground squirrels. He gets them over 100 pretty routinely. Several at just under 200. It's a custom .257, shooting 80 gr. cast bullets. Seems to do a LOT better than the wimpy little .30 cal with diabolos. ;)
 
Classifieds is certainly one place, as most are custom. But from a manufacturer/designer, there are a few. Extreme Big Bore will do a .257 in rifle form, 4500psi; RL Airgun will do AF Condor based, though mostly constructing and not sure how much tuning; RJ Porter and maybe Doug Noble worth checking out. Wicked Air Rifles may also have theirs out. Inovairtech tech makes one, cartridge based. Professional Big Bore may also do it, given they use TJ barrel configurations, 3000-3500psi fill tune in traditional stock.