I guess it really depends on the condition- it looks like those were made in the 70's so i'd want to take a really good look at it, blowers are simple though. Supposedly they were well built - better than home owner grade, less than the pronovost, normand commercial grade.
as for pair it with a L3560,
Its a 2 auger 84" blower with i think a 26 inch fan so it could be done- probably better on the hydro trans (28 pto hp) than the gear (29.5 hp but i think it would be slow and would tax the tractor if you needed the twin auger (deep)- I am using 35 hp to drive a 74" single auger blower with a similar fan and it is below the recommended hp (40-70) but does a good job, i would however not want less power
I also imagine its pretty heavy.
I think a 2-auger would be ok. We use a 516 (single auger) on a 40 hp tractor and there's enough power. I think I gave $250 for the blower. A 2-auger model would be a little heavier but would work fine. On a machine that has been unused for awhile, check there's oil in the gearbox. The fan on these can require a 20-ton pull to loosen from the shaft (ask me how I know) The 516 got a drag blade and new paint added later. Still going great.