While you're out checking the Bridal shops, stop by the fabric store and ask about a product to soak vintage linens, etc. in. I can't recall the name of it, but have seen samples of items washed with it. That might be your best approach to the yellowing you mentioned in your original post.

Our daughters wedding gown came back from the dry cleaners nasty looking. Kind of a yellowis gray color. She wanted me to make a Christening gown out of it. I tossed it in my washer on a short delicate cycle & it came out beautiful & white again. I figured it wouldn't make it any worse than what it was.

I wasn't done talking to you when my fingers just hit the reply button. Anyway, I have made several ring pillows & I always put Velcro on the end of the ribbon & the underside close to the top where the bow is. I just make sure it is long enough to fold backwards with the rings on it.