If you want to tinker with PCIe FPGAs I would rather look into DMA Cards developed for PCIleech, Nitefury/Litefury boards or Alinx boards.
All of these options can be had for ~100$.
been looking for something like this, thanks!
LOL. What does it do? DMA Gladiator, FPGA DMA with Custom Unique PCILeech Firmware
For cheating in games?
There's also the ex-Azure catapult cards someone RE'd: https://j-marjanovic.io/stratix-v-accelerator-card-from-ebay...
The nite/litefury boards are 100% the best starting place though.