Due to the rapid advances in the development of quantum computers and their susceptibility to errors, there is a renewed interest in error correction algorithms. In particular, error correcting code-based cryptosystems have reemerged as a highly desirable coding technique. This is due to the fact that most classical asymmetric cryptosystems will fail in the quantum computing era. However, code-based cryptosystems are still secure against quantum computers, since the decoding of linear codes remains NP-hard even on these computing systems. One such code-based cryptosystem was proposed by McEliece. The classic McEliece cryptosystem uses binary Goppa code, which is known for its good code rate and error correction capability. However, its key generation and decoding procedures have a high computation complexity. In this work, we propose the design of a public-key encryption and decryption coprocessor based on a new variant of the McEliece cryptosystem. This co-processor takes advantage of non-binary Orthogonal Latin Square Code to achieve much smaller computation complexity and key size. We also propose a hardware-cost efficient, fully-parameterized FPGA-based implementation of the co-processor to perform fast encoding and decoding operations. When compared to an existing classic McEliece cryptosystem, we observe a speed up of about 3.3 ×.