Specialty screws

[OregonNed]

I'm getting ready to add some polished billet marker light frames to my truck, and wondered if there were any options out there for aftermarket, stainless screws. I think what I would like to do is use them in the attachment of there - something with a Hex Head, or something else - just to keep someone from simply removing (stealing them) with a simple Phillips Head screwdriver.

Thanks in advance!