let’s separate the OP’s needs from the massive swathe of blue badge holders who are fleecing the system because they get weekly headaches and are classed as disabled.
Cycling offers huge benefits to less able people and these are often overlooked in favour of easier ‘boxes to tick’ for charities/local authorities.
The reality is the cost of such bikes and the very specific needs of the ‘rider’ make mass production bikes very rare and expensive. I used to work in this industry and the average bike would cost £6K, albeit a premium powered cycle and built to high quality but the benefits were immense.
I used to drive the length and breadth of the country in a 3.5ton Sprinter with £50K of demo stock in the back and do demo’s to all sorts of people. From 3 year olds with cerebral palsy who needed a trike with lots of supports on the seat etc to 70 year old stroke victims looking for a relaxed recumbent cycle to get fit on.
One thing was common was lack of funding. Most occasions I left a copy of a quote and they would write off to various charities or the wealthier people would buy them there and then but there was still plenty who were wealthy but expected a charity to cough up.
Either way we should all be doing what we can get anyone not able to cycle enjoy the sport we all love and let them feel included.