A quick search pulled up this thread: Boler cushions and covers
. It doesn't have a link to a particular upholsterer in Vancouver, but has some good information. You can find other threads using the Google site search (blue bar under your login info, "Search," and scroll all the way down to the bottom).
I also thought about the possibility of ordering covers from Scamp
and sourcing the foam locally or online. Their covers are currently $390 + S/H and include the back dinette and front sofa: Carpet & Fabric : Cushion Covers Full Set of Seven No Foam
. They aren't fancy, but they're functional and sturdy. Based on the above thread, they should fit your Boler… perhaps others could verify or correct.
Of course, you may have something special in mind. Good luck!