I've found a Chinese supplier for the board: 100x100mm, 4 layers, ROHS-compliant, less than 400 holes, SMD solder on both sides, silver plated (ROHS demmand), 0.1mm spacement high-density traces. ~280 USD, without shipping and custom fees!
Brazilian industries take advantage of the custom fees (~107% !!!) to sell prototype boards for the price they want (a bit less than imported ones).
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For people whiling to learn about how to make your own accelerator, and starting with a good electronics acknowledge, read:
Lucas/Francis project;
then Freescale's 68000, 68881/2, 680EC020, 68020 and 030 datasheets. Also DRAM memory principles and controllers, CPLD, GAL/PAL & PIC datasheets and programs. That's for start...
Oh, and also you need to learn a PLD language, like verilog.