I could try begging my brother, who does some woodworking, to make the rack for me now that I know it originally had one. It might take some doing, since he sees no value in "old stuff" as he calls it.
Angela, it is tricky to make a new “bow” from scratch with the 1st problem being to find “old” oak boards to make it out of. And it’s a hassel to try to stain newly sawed oak so that it matches the older original oak.
Anyway, since I assume you are not in a big rush to “get er dun” …. what I suggest is that you start “checking out” all antique shops, used furniture stores, garage sales, local auctions, etc. …..
looking for an old, beat up, dilapidated, ….. cheapy ….
old oak dresser with a mirror “bow” still on it ……. or just the mirror n’ bow by itself. (See picture below)
And if you find one then you can ask your brother to “re-size” it to fit your washstand.