$ pacman -Ss pycrypto
community/python-pycryptodome 3.9.7-1
    Collection of cryptographic algorithms and protocols, implemented for use from Python 3.
 community/python-pycryptodomex 3.9.0-3
    A self-contained Python package of low-level cryptographic primitives
community/python2-pycryptodome 3.9.7-1
    Collection of cryptographic algorithms and protocols, implemented for use from Python 2.
community/python2-pycryptodomex 3.9.0-3
    A self-contained Python package of low-level cryptographic primitives
pcr/pycryptopp 0.7.1-1
    Python wrappers for the Crypto++ library
pcr/python-pycrypto 2.6.1-3
    Cryptographic primitives and algorithms for Python
pcr/python2-pycrypto 2.6.1-3
    Cryptographic primitives and algorithms for Python

From https://www.pycryptodome.org/en/latest/src/introduction.html:

PyCryptodome is a fork of PyCrypto.

From python-pycryptodome PKGBUILD:

  conflicts=('python-crypto')
  provides=('python-crypto')
  replaces=('python-crypto')

Unless there are good reasons to keep pycrypto, we should remove it.

Another candidate may be [pcr/pycrptocpp]. I haven't looked at it yet. The only thing I've checked is that the last commit was in 2017.