You should be ok with your boat, just mind the wind in the wider parts of the river, can get tricky, but lots of little bays to get out of the wind...should be great fishin'
There are worms for sale either at the Esso right at the twin bridges at Coles Island, or a bit further south (towards Sussex) at Long's Creek, tiny little gas station/store beside the highway. The Esso also carries a few hooks, lures, swivels, etc...
However, you'd be better off to come prepared. Sometimes these guys run out of worms, and their selection of gear is VERY limited to say the least. Still, they are there if you need 'em. Check and make sure the worms are alive and in good shape before paying for them.
A very important consideration, at least in my case, is that there is a beer/ice store on Hwy 10 just a few kilometres west of McCready's (Coles Island) and in beautiful downtown Cambridge-Narrows at Nan's Store.