Hi All, I'm converting an old Norco to a single speed, and need to find replacement brake levers. Currently, the bike has drops, and grip brakes with DiaCompe "calipers" (for lack of better term). I want to keep the drops, but change the brakes to be normal levers on the flats. I learned that you need to find brake levers that are compatible with canti/road style brakes because they are short pull, while anything listed for V-brakes are long pull.
Any suggestions for levers that won't cost me a fortune? (In Canada)
the handlebars are 22.2mm diameter.

You can use interrupter levers like these. Just terminate the cable at interrupter lever instead of the at a regular drop bar. Alternatively look for “road flat bar brake levers” like these. The only issue there is that they may not go around the curve of the drop bar. There are some out there that are hinged but I can’t say which ones.

Having your only brakes on the tops of drop bars isn't a great idea - braking from the tops is fine for gentle "routine" braking, but not great for control if braking hard or in an emergency, and if you're not set up for emergency braking (ie, for those situations that come out of nowhere), you're not really set up for braking. I second the addition of interruptor levers for the tops - that way you can brake from the tops all you like, but have the "proper" brakes on the drops for maximum braking power and bike control when you really need them

I'll second Cyccommute's suggestions about what to look for, and Litespud's advice to not have your only brake levers up top. I'd either do interrupters or drop levers only.

If the tops are where you think you will be most of the time (enough to justify having your only levers there), I'd consider going with a flat bar.

Just my $0.02.