Are there old souls (actually manifesting old soul age) who are living a so called normal family life, married with kids etc, with a job to provide for the family and actually feeling happy that way.
Good question. I'm sure there are plenty of old souls living this way. In fact, from the MT members that I know of/read about, I was a little surprised that so many were married (and often long-term marriages), had children, went to church, etc. The church/religion thing really surprises me. I know, even MFM "founding members" reconciled the MT with churchgoing, but it still surprises me.
My understanding was that the late-level old soul really didn't have much interest in all that anymore. That the old soul didn't really participate in "society" any more and was often nomadic. I guess I need to read it again, because that doesn't seem to be the case with the MT members, many of are late-level old. 
Living on the physical plane is about living on the physical plane. I know that sounds circular, but the point is that families and society are part of life as human beings on the physical plane. So is not having a family, or withdrawing from society, however you're not going to pass the "final exam" if you don't take the test, which is living a normal life, meeting the challenges head on and surmounting them with aplomb. That doesn't, of course, mean that the final life is going to look like the Young soul success fantasy, the Mature soul angst and drama or the Baby soul "upstanding member of the traditional community." It's going to be highly individual.
As far as church goes, there are churches and there are churches. The membership in my Unitarian congregation happens to be around a third "nature religions or similar," for which read neo-pagan or similar. This probably isn't what you were thinking about when you said "church." I know of several other denominations that are heavily magical in orientation or very spiritual.
