Well, the number "77" is likely a unit marking from some place this carbine was deployed at, my Inland rack grade from CMPhas white paint with the number 55 on the pistol grip of the stock.
If the bore is decent, even with an import mark, that price probably isn't too bad, the pictures of the stock look pretty decent, the bore looks good, the muzzle wear isn't bad, even with a non-military 30.06 round. Depending on your area of the country, that might be as good as you'll see locally.
The import mark only matters if you're buying it for a collectible firearm you plan to make money on, if you're just getting it for a shooter, that mark doesn't mean squat.
Don't take everything the CMP site has to say seriously, they're telling you it might be a long wait time, and that the condition might be horrible as a CYA. It may take some time to get yours, depending on the volume of orders they have to fill. I ordered one on Christmas Eve, got it on 21 January, so clearly they fill orders faster than they say on their page. They downplay condition so if they do send you a total POS, they warned you it could be, but I've yet to see a customer who was really unhappy that they didn't make it right, either with a new stock, or another carbine to replace the first one they got.
And the kicker is, if you buy from them, the profits they make get recycled into shooting programs all across the country.