FWIW, I rigged up a home-brew (and considerably larger) easy-on/easy-off basket for my Dahon Hon Solo; simple, rather crude, but very effective.
I used a basket from Target or Office Depot designed as part of a home or office storage system; it's large enough to hold 2 full paper grocery sackes side by side.
I cut and shaped a piece of wood from a 2X10 plank to snugly fit into the middle space of the rack platform, and bolted it to the underside of the basket so as to position the basket as close as possible to the rack "tombstone". The forward lip of the basket, which is slightly flared at the top, sits up against a Carradice SQR block (I also use a Junior and Camper when these are more convenient) so that the basket can't tilt forward, and a toe strap at the front of the basket prevents it from lifting up backward. But a second toe strap at the rear would suffice to keep the basket in place even if the forward lip didn't press against the SQR.
The virtue of this system is that the block keeps the basket from sliding to either side or fore or aft, and the straps just have to keep the basket from lifting -- far better than trying to lash the unmodified basket to the rack with 4 toe straps.
Someone in the randonneur business makes and sells little QR clips that clamp to rack tubes; these are meant for rando bags and front racks. I had thought of using 4 of those, but they're not strong enough to be the sole means of securing the loads this basket sees. But with the block holding the basket in place, the clips would simply keep the basket from lifting and, I think, be easier to click on and off than strapping the front of the basket with the toe strap.
I can't remember who this person is, or where his website is; does anyone know? IIRC, they cost $35 each.
Thanks