Hi folks,
Same experience with calligraphy supplies, and yes I also just try to buy in bulk (or stock up during a trip down to the US!). I found PIA to be cheaper for shipping than JNB- but it's been a while since I've looked...
I'm in Toronto, and can buy some* supplies from Aboveground Art Supplies, Curry's, Gwartzman's, and DeSerres. The variety of products is lacking, but below is what I've found for inks --
*I found sumi ink in Gwartzman's and The paper place on Queen St. I found Pearl Ex at DeSerres, but otherwise all the above carry FW inks, Higgins Eternal, windsor & newton...oh, and I found Dr. PH Martin's bleed proof white at Gwartzman's recently
Nibs are generally hard to come by except for some hunt options mentioned by crooked spruce. I order them in bulk online
For envelopes (I'm sourcing a bunch for clients), I still find it cheaper to order and ship from the US- I use Paper Presentation. I ordered their sample book, which was a bit expensive but totally worth it to colour match. I find the weight of their envelopes and finish fantastic, better (and cheaper) than any option I've found in Canada (even with the current exchange rate!!) Envelopes usually end up being $0.50-$0.52 for A7 size all in (taxes, duties....)