An apostle is, per the Greek ἀποστέλλω (apostollow) - that is, sent out. It is a job, not necessarily a title. Jesus, in the Great Commission of Matthew 28, literally apostolt (ie commissioned and sent out) all of his followers by telling them:
Go ye therefore into all the world...
While Matthew 28:16 says there were only 11 people there (all his disciples), Acts 1 then goes to add Matthias, becaue the 11 disciples themselves thought a 12th should be added to their number, in order to match the 12 tribes. Later, some have questioned if God had intended to add Paul as the 12th to their number. Regardless of who was in attendance, however, many, many Christians - indeed just about all with a strong missionary bent - now take Jesus' words as being a "Great Commission" that applies to all his followers, not just the 11 in attendance.
As to the fact that many are called to be apostles, we have Paul's word on the matter:
Now you are the body of Christ and individually members of it. And God has appointed in the church first apostles, second prophets, third teachers, then miracles, then gifts of healing, helping, administrating, and various kinds of tongues. (1 Cor 12:27-28)
As such, the answer to your question is a simple Yes - because it is a gift given to all.
The difference, I suspect comes with whether or not there are more big-A "Apostles," by which you mean, did God confer some magical fairy dust and make them special. The answer to that question is far more nuanced. Protestants will say we are all Saints. Catholics will say that some are more Sainted than others. But we'll all say, if given a list, that the "12 Apostles" are drawn from Jesus' named disciples, minus Judas. This is an artifact of history, in the same way that Abraham Lincoln may be a great President, but he's not a Founding Father. Likewise, I'd argue John Champe is a founding father, but you've probably never heard of him.
Paul calls himself an apostle many times but is not included in the list of the 12. One would suspect he would have also called Barnabas an Apostle - but his name does not appear amongst the 12. The list of 12 comes from the tradition of the disciples being sent out, but the job is more widely dispersed than that.
The list is thus fixed by tradition, and because it is a fixed tradition, is finite and known. But as to the gift of apostleship - yes, there are many, many more. And it is the role of the church for those who have been "sent out" to actually act on it.