I work for one of the big lfe insurance companies (in the IT department, so I don’t make the decisions) but will ask on our work forum as there’s usually some knowledgeable people who might be able to point you in the right direction. Saying it’s illegal to sell you if you were over 50 sounds like they were trying to sell you an over 50s plan, not traditional life insurance.
The over 50s plan is one that has no checks on your medical background - the downside is that it’s usually more expensive than traditional life insurance. That’s a general description by the way, there are a few more rules around it.
Traditional life insurance can be taken out by the under 50s as well but they will ask about your medical history. The cost of life insurance is all based on statistical assumptions about how likely you are to die during the policy (sorry to be blunt). If it looks like there are medical reasons for you to die earlier than someone without those medical reasons that they’ll either charge you more or say they won’t cover you (if they charged everyone the same or covered everyone then there would be loads of people taking out cheap cover when they find they’re poorly, paying a couple of premiums and getting a huge payout).
It sounds like you’ve gone for the traditional life insurance, but they should be able to tell you why you were declined. I’d be suprised if it was the MS, as it isn’t life threatening, though the statistics show it may reduce your life expectancy a little bit. The stroke might have been a reason though not necessarily.
It’s worth shopping around because different life insurance companies make different statistical assumptions, but you should expect them to get a full medical report before they make their decision. Also different companies have different approaches to illness and how they sell their policies.
One thing you could do is talk to an independent financial adviser who should be able to help. www.unbiased.co.uk lets you find one near you. They should have a better idea who you might be able to get a policy with. They will get paid commission on your policy, so you shouldn’t have to pay a fee. The fact that they get paid commission doesn’t always mean they are more expensive than finding your own policy on line, though it can do.
Good luck, and I’ll post back if anyone from work has any other suggestions.