I was sceptical if there would be such a thing, but a bit of digging gives-
https://www.discoverjura.co.uk/
(on a personal note it is lovely to see Alex now running tours, for many years the family ran the island public bus service very well before the contract was given to Garelochead Coaches on an underbid, how an outside company underbid islanders is a mystery and was a travesty of justice). Garelochhead do a good job, I'm not criticising them in the slightest. At least, unlike on Mull, there wasn't a bus war when a similar thing happened there and at one stage three competing companies ran on identical timetables- the old island company, the contract winner and another unsuccessful tenderer. On Jura Alex bowed out gracefully.
and https://juraguided.com/
I'm not a tours kind of person, so I'm not recommending as such, just passing on what I can find.