The CORE is a long slide. If you were to find a CORE slide, you will have issues with the sear (different shape & break point), trigger bow (USB), and upper striker blocker being out of alignment (timing). As suggested, either mill your slide, or just get the CORE. FWIW, the Tijicon has a smaller viewing port and is expensive. The Delta or C-More are larger.
If you are just looking for a non-IPSC gun, you can add the Apex forward set trigger to it as well. I have one set up with all of what you are looking for (Apex trigger 1.7 lb, Burris FF3, overtravel screw installed, USB removed). It is an accurate shooter and I barely use it. I occasionally use it as an IDPA SSE gun. Search out my threads and you will see what I tried to do with it as an open gun.