The people who make the Dorsi-Flex also make a boot:
Therapaw dog boots
We used the boot because it is thick and won't wear through but it is also heavy and after a couple of months he could no longer pick it up so it actually caused his toes to drag more.
We then went to the Dorsi-Flex Assist:
Hindlimb Dorsi-Flex Assist
It works well but with both the boots and the Dorsi-Flex you need to watch for sores from rubbing. I ended up using vet-wrap under the boots to prevent new sores from developing.
We were still working on his original boot sore at his end a year and a half later.
If you do try the Dorsi-Flex please note that there are screws on the toes. They will drag on your floors and leave scratches. I purchased those plastic cap things that snap closed over the screw head to save my floors.
I really wanted to try the Biko Brace:
Biko Mobility | Animal mobility & fitness products
There are elastic cords which run from the lower leg to a harness. It looked to me like it would help by pulling up and forward at the same time. I tried hard for a couple of months to order one but he ran out of time before I got one to try.
At the end I had a pile of boots which I offered up on a DM forum.
Best of Luck
DaveJ & TuckerJ