I’m not into FPGAs myself, but this seems to be interesting: An Intel 8080 replica based on reverse-engineering the Soviet 580BM80A clone of the i8080A microprocessor.
The Git-repository doesn’t only include two implementations in Verilog, but also the schematics in PCD-2004 sch format and as a PDF document.
From the ReadMe:
The project provides two i8080 models in Verilog - the one is pin-compatible with original processor and other is refactored to be implemented within SoC and has the Wishbone interface. Both approaches are proven on the real boards and FPGAs. The models are compact and fast enough, the typical speed and area for Wishbone-featured model on the DE0 board (Cyclone EP3C16F484C6):
104MHz clock, 607 LUTs and 187 flip-flops, no RAM blocks
The following are listed as supported FPGA boards: Altera DE0, Altera DE1, Altera DE2-115, Alinx AX309.