My fiance is 48 and I’m 50. It will be the first marriage for both of us. There is nothing embarrassing about it. If someone were to ask what it feels like getting married for the first time at this age, the response would be that it was worth the wait.
As for the rings, I suspect that a jewelry store attendant isn’t going to bat an eye at the age of the purchaser. They have probably seen and heard every situation under the sun.
There are two situations where I can think of age being a factor of embarrassment when it came to a marriage. One is if there is a severe age gap. The other happened to a school friend. When his elderly father died, his mother married his uncle (his father’s brother). “Hi, meet my cousin Tom. He’s also my step-brother.”