Good straw (dense bales, pre-seeding, weed-free) will go for as much as if not more than hay. We do a brisk business in quality straw; good quality grass hay is around $5/50lb bale in my area, we sell the straw for $7/bale, with discounts for quantity.
Mango is right that it’s the wrong time of year to buy straw, and also correct that depending on his needs, he might be better off just buying out last year’s mulch/crap hay supplies, as it IS the right time of year to be doing that.
Most of your larger local hay guys should know who does straw, as well as any of your larger, locally-owned garden centers. (Who may be able to either get that quantity in for you, or send you straight to the source.) Craigslist can also be a viable place to look. Your issue will be the quantity, at this time of the year.