I paid $620 for a 14-3 8-3/8" barrel in 98% condition with no box recently. I have also wondered what percentage of the Model 14s had the long barrel.
$800 is high, but the one I bought was listed at $799, so there may be some wiggle room. You haven't said anything about condition, just box & tools, but I assume the gun is in high condition for that kind of price.
But really, this gun will pay for itself, because you can buy MUCH SMALLER TARGETS. I just buy little stick-on 10-rings now, LOL. You'll love it.