You will need an "E12" socket - find it in a set from Lisle Tools (which, I believe, Sears carries. Also, check the better-stocked small local parts houses.) Using a 12-pount socket can slip, if you're not careful (and the thing fits just right.)
They are threaded 3/8"-16, so take them to the local and match the underhead length. Head style is not critical - you can use a hex head, socket head (hex/Torx,) or even a stud (which I do.)
Keep both internal and external Torx sockets handy - you'll need them on other jobs. The good news is that most of the screws use a standard thread (either SAE/inch or ISO/metric,) so you can replace them if you need to.