Apostolic Succession and Denominationalism

First, I'd be careful about how much weight you hang on apostolic succession by laying on of hands. Depending on how we define it, it is a valid concept. And ordination is normally accompanied by it. But this does not imply that ordination is invalid without it.

For example, no on laid hands on the original elders of Israel when the office was instituted (Num. 11). Rather, they were confirmed in their office by a "placing" of the Holy Spirit, with no mention of laying on hands. Similarly, Jesus commissioned the apostles without laying hands on them. If we can point to any particular text of commissioning, Jesus' preferred mode seems to have been breathing (John 20:21-22).

In fact, we have precious few — if any — scriptural examples of hands being laid on anyone for ordination. Yes, hands were laid on people at various times. But It is far easier to point to people who were ordained without the laying on of hands than with the laying on of hands. And in none of the available cases are we told that laying on hands is a necessary part of the process, or that it transfers apostolic authority. Is it a good practice? Can it result in spiritual gifting? Yes. Is it necessary for valid ordination or ecclesiastical authority? Not according to Scripture.

In general, Protestant churches reject the Roman Catholic formulation of apostolic succession because of its unscriptural basis, as well as its attachment to the magisterium. There is nothing in the Bible that says the authority of the apostles can be passed to another by laying on hands, or that we have an authoritative tradition that is somehow passed on through laying on hands. In fact, there is nothing in the Bible that says apostolic authority can be passed to another by any means. So, Protestants tend to emphasize apostolicity — fidelity to the teachings of the apostles, as found in the New Testament.

That being said, many Presbyterian denominations can trace their own heritage through the laying on of hands from presbyter to presbyter, usually going back through the Church of England or through a church of the Reformation started by former Roman Catholic ministers. For instance, John Knox and John Calvin were both ordained in the Roman Catholic Church. If it of great concern to you, I would advise you to ask each denomination you are considering — but keep in mind that since it is not a big deal to some of them, they may not know the answer. You mentioned that you are currently in the PCA. The PCA came out of the mainline PC church, which I believe can trace apostolic succession through both Scottish and English sources. There are also many other denominations that claim apostolic succession: obviously the Eastern Orthodox churches and the Church of England, but also many other churches that came out of the Reformation, the Church of England, and Scottish Presbyterianism.