Annie, After two years on disability, my husband was automatically put into the MEDICARE. Age was not a factor. They've been paying most of his medical expenses (he has aarp supplemental policy)for about 5 years and he just turned 60. If you don't have it already, be sure to get a prescription for the power chair from your doctor if you want insurance to consider paying for it.
Unless your husband has an objection, I would apply for disability in your state asap. The medical professionals we've worked with all prefer if you are on medicare, not because they are trying to abuse the system, but because it means they can order what they want for their patients right away and not have to beg and fight with an insurance company. Best wishes to you both.
Diana in Laramie