How do I get tests for dyslexia without going through the school system?

Educational psych. There are a variety of testing resources but these may be limited in some areas. The scottish rite hospitals may have a program in your area. Educational psychologists are often available to do the testing but this is labor intensive & can be expensive. Some test on referral by your dr & some accept self referrals. Many insurers do not cover this type of testing or require you to use their source.