When you Export from Lr, you can select File Settings/Color Space and choose any Profile which is in your ColorSync Folder.
ColorMatch (which was originally a profile for high-end CRT monitors that were used for PrePress about 20 years ago!) should be present in your ColorSync folder.
If it isn't, you can probably track down a downloadable version from the Web.
If you've got Photoshop, you've got ColorMatch RGB installed on your system and can therefore use it.
A tad bigger gamut than sRGB, the 1.8 gamma is preferable for those in CMYK workflows.
Ahh, thank you all. I was looking in the wrong place. I expected to see it in Preference>External Editing. I didn't initially see it in Export because the default is the three colorspaces. You have to choose Other... and toggle the colorspaces you want to use beyond those three. Thanks for the heads up. Makes sense now.