You may find that they have to get them shipped (I think they're from Thailand or somewhere like that) .. might take a few weeks but are worth the wait.
A bit wider than the 175's and would be slightly taller too giving you slightly higher gearing.
Here's where I got mine from. 185R13 maxxis 17 mm whitewall
£75+VAT (our purchase tax) = £90 each (about $145 each) .. although we tend to get ripped off on price over here so hopefully they'll be cheaper for you.
Any idea what the ideal pressure is for that size tyre? .. I put about 27psi in mine,, I think the original spec was 24psi (assume that was for cross-plys though)
There's something reallllly nice about a new set of tyres!
Let me know how you get on