Sounds like good pricing! The BB1560 box blade is what I'm running with my B2650HST rops tractor, basically the same base tractor as yours, with your quote being on a BB1260. I recommend the bigger (taller) box scraper that I have, if only that the added box weight helps it engage the ground more positively, and as rear ballast the added weight really helps with FEL and forks work. The BB1560 is about 80 lbs. heavier than the BB1260. With my BB on, there's nothing the forks or loader can lift that it's not enough ballast for.
How much snow will you be getting? A few inches now and then with a rare big dump is ok with a loader and/or the rear blade you're getting. But IMO, with yearly multiple 6"+ snow events for example, a front mount blower beats all. Especially good for leaving no snow banks buildup ever along the drive edges.
And again IMO, with the box blade and only 200 ft to maintain, there's no need for the rear blade for the gravel. So get a front blower instead of the rear blade?
Any way it goes it sounds like you're in that tractor/implement shopping zone, I spent many months at that, maybe years, and the final new equip quotes mean its getting close! Have fun!