Generally HP ammo is WAY more expensive than FMJ RN, as it has no real purpose in paper target shooting (More along the lines of 'Murican self defense). Like Paul_T said, 115/124 grain FMJ ammo is the cheapest bulk ammo you'll find.
Tenda out of Ontario often has Blazer Brass 9mm (In 115 and 124 gn) on sale for pretty good prices. Shipping is reasonable too. I've bought the majority of my 9mm from them. The Blazer Brass is made by CCI (Incidentally, Speer is made at the same address), and I've had zero issues with it. Can't really comment on accuracy, as I've only really shot it at close range at steel challenge matches. No complaints though? When I miss, it's me haha.
Western metals here in Calgary also has decent prices on remanufactured 9mm. They do (Or did?) a 9mm on the 9th of every month sale, although they haven't mentioned it in a while. I've only shot maybe 1000 or so rounds of their ammo, but again, zero issues.