These guys? http://www.totallysportsinsurance.co.uk/
Given it’s ring up to discuss and tailored to individual, I bet it’s not cheap.
Being self employed though it’s an interesting area, though awkward with me as time off work you have to prove you may have had £xxxx income in that time which is purely a guess and they might debate it. Last time I had extended time off due to injury I just covered it myself through my company, but if it was more serious then perhaps I should have some better cover. I do have life insurances of sorts that will cover some income, mortgagee etc, though they won’t pay much.