While I work in downtown Toronto, my home is just outside the City of Toronto, to the west in Mississauga. So not sure about where to get Orange Pineapple as a cone in the actual City of Toronto. Lots of places to buy good ice cream in cones or tubs, but I haven't gone looking specifically for Orange Pineapple. My normal go-to place is Hewitt's Dairy Bar when we are in the area.
You can buy the 2-litre tubs of Chapman's ice cream in many supermarkets, but they tend to stock the most popular flavours for turnover reasons, so I only rarely find the specialty flavours like Orange Pineapple. And if they do stock the less usual flavours they tend to sell out quickly, IME. I grab it if I come across it! I have only found Hewitt's at their retail outlet. If they sell it elsewhere, it may be to the specialty and restaurant trade.
Chapman's Dairy is headquartered to the northwest of Toronto, in Markdale (about a 2-hour drive from downtown Toronto), but I do not believe they have a retail store. Hewitt's Dairy is headquartered and has a retail store in Hagersville (just over an hour's drive from Toronto), just south of the City of Hamilton. Hewitt's could be done as part of a trip to Niagara Falls or the surrounding wine regions with a bit of a detour.