OP check with the school nurse since you have no vision insurance he might qualify for
free glasses
Some states an walmart has paired up to get FREE glasses to kids without vision insurance which was one of the few things my kids ever qualified for as there was no questions about how much money daddy made or anything.
It was the cheapest frames that was free but I was allowed to pay the difference to get DD a more expensive pair....usually the next step up from the cheapest frames. I never had to pay more than 10 or 15.00 out of pocket.
Believe me you can pay big bucks for frames...while I don't usually care for Walmarts cheapest frames (usually out of style frames that did not sell well) there is no dif that I can find over their next priced frame and the most expensive frames out there.
Just because you take son to any eye doctor does not mean that you have to get glasses there the doc can write the prescription an you can ge the glasses at the eye place of your choosing.
Knowing kids an glasses I would suggest getting the glasses close to home because glasses do need adjusted and repaired from time to time esp with young boys which was another reason why I liked Walmart for kids glasses the glasses department was open daily including Sundays an someone can adjust the glasses anytime the department is open. So usually no need to take time off from work to go down an get glasses adjusted an maybe have to drive across town or to another town miles away because that is where you got the glasses.