They exist. My entire house is 3000K.
You can buy whatever Chinese brand is on Amazon this year (in my experience they change brands about the same time the bulbs start burning out), or try your local big box stores. I do believe Philips has some though, and they’ll last longer.
Edit: Just Google it.
This 4-pack actually has multiple white options in each bulb, including your desired 3500K: https://www.amazon.com/Philips-LED-Flicker-Free-2700-5000K-576314/dp/B0B8TNK47C
Write in pencil.