How funny, our 10 year anniversary is in November as well! I have been thinking about a gift, and have decided on a three stone ring, but with a pink colored center stone. I thought it would take me months to find the perfect stone, but I got luckily and fell in love with a custom cut emerald cut pink topaz. I shipped it off to Whiteflash and am having them design the three stone, with diamond traps on each side of the topaz. All in, slightly over your budget but not by much. I will wear it as a right hand ring. I wanted something completely different from my engagement ring, which is oval bezel with a micropave halo. I have never owned anything step cut before.
Anyway, sorry to ramble, and not sure if you are into colored stones or not, but that could be an affordable option. I have 2 girls too, so pink was clearly the front runner for color!