k la, i try not to be as mean as possible...
but going by the stuff thats not easy to change...unlike the easier stuff that can be changed like those fugly knobs and tuners...
that is one fugly top for a custom, ie. its too fugly to be real.
customs also have ebony fretboards, yours has what looks like rosewood.
the bridge style on your guitar seems based on the nashville, which was only introduced from the mid-70s onwards.
and since its established that its definitely not a gibson, i would say its more likely a jap copy from the 70s.