Can't you just create your context with CONTEXT_COMPATIBILITY_PROFILE_BIT? This will ask for a compatibility context, which supports all deprecated functionality (including OpenGL 1.1), so you should be able to plug in this library without any modifications.
Although support for the compatibility profile is optional, I don't know a single implementor that doesn't support it (that's unlikely to happen any time soon, too). In fact, I remember a guy from nVidia holding a lecture once (some title like "What's new in OpenGL 3") which basically advised to always use it because your programs don't get any slower and most/all of the deprecated functionality is well-supported in hardware anyway, so there was no reason not to use it. I'm somewhat disinclined to agree with that statement, but if that's an official statement from an IHV, then that's what it is. They gotta know better than you and me.
Found it, that "nVidia guy" was Mark Kilgard, see page 97:
Lots of easy-to-use, effective API got labeled deprecated [...] Best advice for real developers: Simply use the “compatibility” profile.
No, your program won’t go faster for using the “core” profile. It may go slower because of extra “is this allowed to work?” checks.