Touch Math has a decent track record with math disabilities. I've worked with teachers who use this, and like it. There is also Marilyn Zecher's OG-inspired Multisensory Math program out there, which has an access model similar to OG's, where you hire tutors certified by the developers. I don't have direct experience with that one.
Many of the multi-sensory math remediation programs mention the concrete-pictorial-representational sequence, which is what Singapore Math and Math Mammoth (for instance) are based on. For most students, difficulty with math facts is based in deficits in basic numeracy skills. These curricula start from numeracy.
Interesting ways you can build practice into the day also include dice and card games, learning to read music (rhythm notation is all fractions), cooking, woodshop/carpentry, etc.
