Yes, but not in a double shoulder rig. I do have an excellent old nylon Weapons Systems vertical shoulder rig for 4" revolvers. It first carried my old S&W Model 58, while an HK P7 rode on the hip, in a Bianchi Askins Avenger. The shoulder rig is flexible enough to handle K- through N-frames, Ruger Speed Six and GP100, and SAA-sized single actions. I haven't owned a P7 since about 1986, so the weapon worn on the hip has varied, from compact autos and revolvers, to a second 4" sixgun and 5" 1911 pistols.
I used to do much long-distance road tripping in the 1980s and 1990s, and guarded auto dealerships while seated in my truck in the late 1980s; a shoulder rig is excellent when seated for long periods. At work, when doing surveillance assignments for eight to 16-hour shifts, that shoulder rig was very handy.
More recently, I obtained a gently-used, pre-owned Andrews Monarch rig for
the SIG P229, but rarely wear it. (I started carrying a P229 as a personally-owned duty pistol in 2004, and started adding more P229s in 2007.) When I carry two SIGs, the second is
more likely to be toted in a Safepacker, from The Wilderness, or in a belt holster. These SIGs were the first duty-sized pistols which I have often worn on the belt in pairs. Even with a good, purpose built belt, however, two SIGs, plus spare mags, can get heavy when worn all day, with both on the belt. It is more comfortable to sling one in a Safepacker.
To be clear, carrying two full-sized fightin' pistols, all day, is not my daily norm, outside of my badge-wearing hours. There have been times I felt the need to up-gun, so a second fighting pistol, and sometimes even a third, has seemed a good idea. Other times, with shoulder rigs in particular, it has been comfort reasons, or accessibility options when
wearing a heavy jacket or rain coat. My second handgun has much more often been a smaller weapon, usually a snubby revolver. My skinny, scrawny fingers are actually quite well-served by the factory grip of a Ruger SP101, and it is very common for me to carry two of them, as a concealed carry combo, especially after I bought one with the longer 3.06" barrel.