Let $G$ be a countable Abelian $p$-group which equals a direct sum of at most countably many finite cyclic groups and at most countably many copies of the Prüfer $p$-group, where these finite cyclic groups all have order less than $p^k$ for some fixed $k\in \mathbb{N}$, and there are exactly $N$ copies of the Prüfer $p$-group. (Where $N$ can be $0$, finite, or infinite.)
Then my question is, how many elements of $G$ are there of order $p^{k+1}$, as a function of $N$?
Are there finitely many or infinitely many such elements, and does this function depend on any feature of the group other than $N$? One data point is that there are $p^{k+1}-p^k$ elements of order $p^{k+1}$ in the Prufer $p$-group.