Good luck with kindergarten for your DS4.5
Hopefully the school will be a good match. Does the school want to modify their program in anyway to meet your son's academic needs?
WISC-IV minimum age is 6 and zero months.
The best link for names of psychologists is
http://www.hoagiesgifted.org/psychologists.htmI guess one way you could go about finding a tester who get's gifted is to call and ask if they do WISC-IV, and ask how many times in the past 3 years they have needed to use the extended scoring. I'll bet you get a lot of puzzled pauses on the other end of the phone.
Asking if the tester is experienced with testing gifted kids doesn't help, because of the problem of those that don't know and don't know that they don't know.
I would check with the school and ask them who the other parents with kids like your kid seem to like.
Also contact your state gifted association and attend some in person get-togethers and make a few local friends. You will probably feel the most comfortable with the parents who have children similar to yours - ask them who they had good experiences with.
If you feel comfortable to do so - state what part of the country are potential places to get tested, and we'll make suggestion.
Love and more Love,
Grinity