That's the difficult bit, it would be something Stepford wife like, ring included. We never really saw eye to eye on clothes (or marriage) and my aunt already made a passive aggressive comment about me being a fashion dolly 😶 (it's her hangup, not mine, it doesn't even land).
I didn't have to overthink it with my mother or other grandmother's funeral, of course I went out and bought something they would love on me to celebrate that connection of a shared love of what clothes can do for you. But I also never wore those items again as they were too associated with the services. Other funerals where I was less close it didn't really matter what I wore, this feels somewhere in between that.
So my options feel like (but probably aren't, it's just useful preoccupation of the mind atm) buy something and get rid of it after, wear something I already own with the risk of it being associated and potentially not wanting to wear it for a while or ever (which feels really stupid, and unlikely, but from experience I know grief isn't all that rational so I can't just shrug it off). I've got a black office type dress on a pile of to be donated clothes which sort of solves all my problems at once but I'm getting rid of it because it feels very dated and it just doesn't feel good on. While that makes the most sense I think I need to be 'comfortable' in what I'm wearing.