Wow, that's a lot! But then again, it's your wedding so don't compromise unless you have to. Keep checking ebay - they have lots of tiara's.
I got some great bargains from ebay - my shoes were brand new (ivory silk dupion with embroidered gold swirls for 99p plus £5 post!), my tiara was less than £5 incl post and has 'hidden Mickeys', Nigel's ivory silk with gold embriodered swirls waistcoat is like new and was £8 total, ivory wing collar shirt (ex Pronuptia) was £7.49 total and gold scrunchie cravat and hankie was £10.95 total, new. I was new to eba before this but now I'm hooked, and got lots of scrapbook stuff as well, including some die cut pumpkin carriages which I might even use for our stationery on the day, as well as scrapbook.
Have fun searching for your dream tiara!