McClellan Rangers? If you were going to give a re-enactment group a "McClellan" name, why not go with a historical example, like the McClellan Dragoons? Of course, that would require the unit be a cavalry re-enactment group. Wonder if any of those exist? Apparently so. Check this one out - an Alabama mountain-Unionist cavalry reenactors' group.
Update: now, I wouldn't call the group bogus, Dimitri. They're technically re-enacting the 104th Pennsylvania, which was a Fourth Corps unit which fought under McClellan on the Peninsula. It's just that the 104th wasn't named after McClellan, nor was it the sort of light infantry, cavalry, militia, or irregular outfit which the name "Rangers" evokes. Fourth Corps isn't even really what you think of when you think "McClellan's AoP core" - that would be more Fifth Corps, you know? I suppose the McClellan Rangers might be making the Philadelphia connection, since both the unit and the general were both produced by the city.
Not that it really matters, I suppose. Different groups have different reasons for the units which they re-enact. I have a friend who's a member of the 9th Pennsylvania Reserves, which has all the color and specific history of Curtin's storied Pennsylvania Reserves. There's a company of the 148th Pennsylvania in my county, specifically because the 148th was also known as the "Centre County regiment", due to it being primarily recruited here in Centre County. There's even a 6th USCT reenactor's regiment down in Philadelphia, largely due to that unit's relationship with Philadelphia's wartime black society, I imagine.