HI, sorry no specifics
but - in the past you could rent Hyundai H1 vans - 9 and 12 passenger
I note a TTOL sponser - Travel Car rental - no personal experience - shows a H1 for rent
So guessing others must also?

Me - I would rent two cars and maybe cab for the odd dinner out if you wanted to be able to have a drink
But you will know what works best for you

Hope it works out - note pretty sure I have been to Harriston and maybe the bakery in the town

J&B