It seems odd that the plow maker HLA tells you that most of the larger plows they sell are with the floating blade, and yet they don't offer that option in the smaller blades. You'll see from comments on here that the vast majority of people who have used a floating blade say it is the better option. Most of those who say float isn't needed have either never tried one, or have relatively flat or paved drives.
I've never tried a floating snow blade on my tractor FEL. I suppose I could go to the 3000 series and put a floating blade on my 40 HP diesel tractor, or I could buy a huge dozer and plow my relatively flat gravel drive with it, but just like I don't need a dozer to do the job, the 1000 and 2000 series plow blades don't need float built into the blade, otherwise HLA would already include it. The 3,4,5, and 6000 series likely could use the extra help and that's why HLA included it where it was needed.
Here are the relevant specs: HLA 7' 2000 series blades are 610#s, with 24" mouldboards, max operating wt: 5K #'s, no blade float, except lateral float. 3000 series start at 1010#s with 30" high mouldboards, and come with blade float, which can be locked off as needed, and more expensive same length blade as the 2000 series 7' blade.
Anyone whose read through this entire thread and made useful comments along the way will hopefully realize that the OP is stubborn in his belief that float will cure all, when in fact fixing his driveway would be the best long term solution to his problems. His choice, his money, his frustration of a 'drive'.
He doesn't want to spend the long dollar investment, his choice; but the plow manufacturers are not at fault for not having what he wants, just because his drive is a one off poorly designed and non-functional mile or so long run through the woods he chooses to call a driveway. I'd call it a back road, not a driveway.
The OP is determined to do things his way- my concern is he's barking up the wrong tree. I'm NOT saying his way can't succeed, just that it's less likely to succeed than what most likely really needs to be done- FIXING his drive, not cobbing a Frankenplow!

:2cents:
BTW, if his Franken plow solves his problems I'll burn my non-existent, 'Make America Great Again' hat for Canadian ingenuity!:drink: