Hardware implementations of advanced cryptographic schemes gain importance for emerging cyber-physical and autonomous systems and with that the need for area-optimized hardware is also increasing. In this paper, we present a scalable, area-optimized elliptic curve ElGamal cryptosystem module that integrates both the encryption and decryption operations into a single block. With the help of the Universal Elliptic Curve Arithmetic unit, that is designed to perform elliptic curve point multiplication, doubling and addition, the area has been kept to a minimum to fit on the Xilinx Spartan-6 LX75 FPGA. The design supports the NIST-recommended curves over prime fields.