My 1960 SS came with 5 various 9 inch blades - rip, crosscut, ply, & then some?. All in a plastic molded box to hold them. I then bought 2 x 10 inch blades and had to get the arbor hole machined to 1 1/4" fit but they both work well. (On a 3/4 horse motor.) The 10 inchers are my first preference, but use the 9 inchers for ply and when the 10 inchers are off for sharpening. The extra (1/2") height is a boon.
I do have the reto saw guards for the 500 and use them with no problem on either size blade.
Regards
Sandy
1960 SS500, Magna Jointer & Dado. Hailing from New Zealand