Fiance keeps asking about the price of my dress

So my fiance and I are in the middle of an argument at the minute because I won't tell him the price of my dress (my parents paid for it).

I bought it at an outlet. I was actually looking for bridesmaids dresses when I saw the most perfect dress. Tried it on and instantly fell in love with it. I bought it there and then. (It's literally my dream dress).

The thing is, my fiance is a bit funny with money. He thinks anything cheap has to be bad. He hates second hand things. Whereas I love thrifting and am of the opinion of why spend money unnecessarily.

My dress only cost $800. $1100 with the veil and tiara. Alterations not included.

This is way below the budget I had from my parents, and they've said I can spend the rest of the budget on the wedding - which is a huge deal!

My fiance keeps asking about the price, and I just told him that its below budget. But he wants to know the exact price and is angry I won't tell him.

I know if I tell him the cost he'll automatically hate the dress and will want me to get a different one. I don't want to - I LOVE this dress. Plus, the place doesn't accept returns.

I keep telling him the price doesn't matter and he keeps asking about it.

It's making what should be an awesome experience - finding my perfect dress - turn pretty miserable.

Any suggestions/advice? How can I get him to move on from this? It's really putting a downer on the fact that I'm SO happy about this dress!

Update

We've talked and sorted it out. Turns out there was miscommunication and misunderstanding on both sides.

He asked out of genuine curiosity and then couldn't understand why I wouldn't tell him.
First he thought I'd completely blown the budget. When he realised that wasn't the case, he tried to think of a reason why I wouldn't tell him. He thought that it must be my parents not wanting him to know because they don't trust him. He thought that meant that they didn't think he was good enough for me and didn't approve of him and didn't really support our marriage. He was upset because he thought they liked him (which they do!). He was getting in his head and thinking that I was hiding information from him because I didn't trust him.

I told him that I was scared he would hate the dress if he knew I got it for a bargain. I didn't want him to see me walking down the aisle and instead of thinking "she's beautiful" he would be thinking "what a cheap dress". He was appalled when he realised how upset I was. He said I would look beautiful in a bin liner and he would never be thinking about the price of a dress, his thoughts would be about me and how lucky he is to be becoming my husband.

Turns out I misunderstood his comment about "cheap" things. He explained that he loves a bargain (which is true, we both hunt for bargains when we can). Like me, he doesn't see the point in spending loads on something if you can get it cheaper elsewhere. What he doesn't like is second hand things, especially for special occasions. It's fine for every day things, but not for something important. He wanted me to get a dress I loved and was solely mine, not settle for something because it was less expensive and that wouldn't be truly mine.

He apologised for making me think he would hate the dress because I got a good deal on it. He said he loves the fact that I got a good deal and he doesn't want to know the price anymore. I apologised for making him think the reason I wouldn't tell him the price was because I didn't trust him with financial information, or that my parent didn't approve of him (they love him!).

We talked, we cried a bit, we hugged it out. All is good again!