I have a squier bullet strat and I bought Dunlop strap locks and it said I had to drill holes in my guitar so I don't want them now. Here are the Ernie Balls,
A lot of the import brand guitars use VERY small strap button screws. Far smaller than adequate IMHO. You will probably have to drill out the holes for any of the aftermarket strap locks that are available. Maybe not for the grovers, which use the smallest screw of all the options.
If your existing screws are the same size or similar and fit correctly in the new strap button you won't have to drill. On my Music Man guitars I use the original guitar screws. But even if you do decie to use the screws that come with buttons (which are probably a little bigger than your stock ones and will be a little more secure) if you have the right size drill bit it's a very easy job because you are just enlarging the existing hole.