I am not sure if Medicaid/Medicare covers pumps (I'm outside of the US), but you *may* be able to get "exceptional" coverage if his doctor writes a letter stating that it is a medical need, and that no other treatment will do. Perhaps different states also have different coverage. Some may cover pumps.
Many pump companies also have a payment plan, which allows you to make a down payment to get your pump, then you pay a monthly amount for a set period of time until the pump is paid off. I have a Cozmo pump. I know that MiniMed offers a payment plan. Cozmo does not advertise it, but they are usually also willing to work out a plan.
Lastly, I would suggest asking his doctor for a pump "trial run". You can also call MiniMed or Cozmo and ask. They will give you a loaner pump filled with saline (sterile salt water) to try and see if it's right for you. I suggest you do this, as insulin pumps require a certain amount of manual dexterity and technological ability to use. All insulin doses and basal rates (constant insulin flow) must be adjusted and programed by the wearer. Infusion sites also have to be changed every 3 days.
I believe MiniMed's site is
www.minimed.com and Cozmo is
www.cozmore.com (Smiths Medical).
Insurance for Pumps 
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