$500k for senior (L5) is kind of the expected offer these days. If you are interviewing at FAANG you are doing a huge disservice by using Levels and settling for $300k when you can pretty easily get $500k.
I joined a FAANG a couple years ago at $550k TC or so at 4 YoE for senior. It's grown to about $950k due to stock growth. I'm not sure what you mean by "I can't touch the money for a few years," I get a portion of it every few months.