Especially for someone that has a Model 1521 Diamond Jubilee, you may want to consider purchasing the matching-colored sand & jade Model B-9/1522* "Floor Beautifier"** at the Buy It Now price of $35 ($40 shipping).
It has both sets of brushes (for carpets & floors) plus lambs wool buffing pads, and the original users manual.
*There seems to have been a miscommunication between departments as literature refers to it as a Model B-9, and the nameplate states that it's a Model 1522. The same is true for the later B-10/1522s (which I own). I'm thinking that the parts were made in Canada, and the assembly and printing were done in the U.S. like other products of the era.
**Some had a "Floor Beautifier" decal, and some had a "Diamond Jubilee" decal.
I'm not the seller (and don't know the person); just passing on a good deal.