For reference, the Inteceptor .45 IS an H&K MK23.

It's called the SOCOM in Metal Gear Solid since one of it's designations IS the "USSOCOM MK23". USSOCOM stands for "United States Special Operations COMmand", though is generally just referred to as SOCOM. The pistol itself IS referred to as the SOCOM Pistol since it was adopted as a primary sidearm of US Special Forces groups, and apparently the name just kinda stuck, thanks to it's notoriety.

As a side note, it's a bitch of a pistol to use if you don't have big hands. It's heavy, and designed for heavy, offensive use. That's why the USP was invented AFTERWARDS- same design, smaller profile, easier to handle. Still makes use of a threaded barrel, but the attachments are different because of the smaller size (The USP is chambered for 9mm, opposed to the MK23's .45 cal).

Now the setup used in MGS IS what people are used to seeing with it in media- the front attachment (and part of what makes the look in MGS more iconic) is a blocky combined module made specifically for the firearm's use.

This is what the Interceptor .45 looks like with the Champion's Suppressor and the Combined Module. It's about as close as you can get currently in the game.

I'd say probably a request that'd get you closer to what you're looking for would be for someone to model out a blocky laser attachment for the Interceptor and add it to the gun via beardlib with the Combined Module as a base. It's certainly doable if one has the modelling skills, I think (I do not, sadly).

Hope this helps clear things up! I for one certainly wouldn't mind seeing something like that happen.

EDIT: Also, for the record, there IS a mod that currently exists for the Interceptor to give it proper H&K markings here on Last Bullet. You can find it here. https://modworkshop.net/mydownloads.php?action=view_down&did=15902 (Not made by me.)