Anyone know where I can obtain online a replacement VRAM for the NES? Current one is the Sony CXK5816SPS-15L. Any compatible RAM is welcome.

When turned on, it would blink to a green screen (checked all connections and cleaned all parts and now it doesn't blink anymore). It now boots the game every time. However, all games have graphical glitches or missing graphics. In some games, the main character does not appear on screen, but the rest is visible. Other times, I see numbers and garbled graphics on the screen while the game plays. So my guess is the VRAM. Can't be the dirty contacts or not making contact since I've troubleshooted that for hours and all outcomes are the same, even with known good.

Any ideas? Thanks!