its hard to find good quality products in a mom and pop hardware store, especially if your staying in the province. it does not make sense to buy a poor quality part just to stop the leak and then buy again a better quality part when you go to a big hardware store like Citi Hardware. it's not just the cost, it's the double work of removing and replacing the valve.
so if your wife tells you to fix it asap :-) he he he ... then better think of a good solution to fix the water leak with minimal work.
why it leaks? the ball-valve inside the unit gets misaligned due to the frequent opening and closing of the valve when you use it. you can easily notice this by slightly moving the lever, the lever will have a large 'free-play' before you feel that the ball valve starts to move. so when you close it again, it does not really fully close. the problem gets bigger (more leak) when you keep on using it because the misalignment gets larger.
how to do a quick fix? for this type of ball-valve (see photo), the off-switch is just controlled by a notch in the lever handle. this is why you can't totally close the valve once its misaligned.
the solution is to simply cut the notch with a metal saw so that you can freely move the lever (and the ball valve) all the way to close it properly even if its misaligned. all you need to do is remove the nut that holds the lever to the valve and then cut the notch with a metal saw and then reinstall the lever again - no need to remove the valve :-).
leaking problem temporarily solve until you can buy a good quality replacement part :-) ... cheers