I once knew a girl that got a fantastic pair of engagement shoes. Bright red heels iirc. :)
You don’t have to get a ring. Do what works for you.
If you’d like to humor everyone, get a very thin, plain stacker band. You can wear it with any future rings (should you go that route) and spend well under $100.
Not sure on color? A cheap set of 6 to try on and see what you think might help!