Landing Site tours from Caen

Can't help you with a tour, but Juno Beach is slightly closer to Bayeux than to Caen (less than a half-hour), and the Canadian Cemetery is close as well. That and Bayeux is just a much nicer town to visit—particularly if you are interested in history.

It would be nice to see Bayeux and I was looking forward to it but we have limited time and just can't see everything so Bayeux is currently not on the itinerary

If your primary interest is the Canadian sector of the Normandy landing sites, I suggest looking at the links provided by the Juno Beach Centre. There may be a private operator willing to pick you up in Caen.
https://www.junobeach.org/plan-your-visit/links/

However the previous posters are correct in that Caen is not a handy place to stay for DDay excursions. We had a car and stayed in Courseulles sur Mer, in the heart of the Canadian sector. Lots of car rental options near the train station in Caen.

Check to see whether Overlord Tours offers something focused on Canadian sites. I know it has several options for one-day tours. They depart from the center of Bayeux.

A half-day tour wouldn't allow you to see much, because so much of that time would be spent driving between Bayeux and the invasion sites.

I've now had a chance to check the OverlordTours website and can confirm that the company offers a full-day British-and-Canadian sector tour that includes Juno beach: Overlord Tour No. 4

I don't know whether that tour runs daily; I'd email and ask if you think the tour might suit you. I'd also ask whether the company recommends participants take a packed lunch with them. On the tour I took of American sites, the lunch break was at St-Mere-Eglise, which is also the location of the Airborne Museum. Anyone who went to a restaurant for lunch probably had to forego the museum.

We took Overlord tour #4 in 2015 and it was really great. We saw some amazing sites. We lunched at Arromanches and had time to explore a bit. Really enjoyed it!