The Arista Edu RC paper from Freestyle has pretty good tonality, responds to Ilford contrast filters quite well, and can be about the least expensive stuff around. It is physically more fragile than Ilford, which I don't mind for contact sheets.

But prices fluctuate, and you have to compare on the basis of delivery to your door (shipping and possibly sales tax). A few minutes on B&H, Adorama, and Freestyle will give you the current price structure. Many, but not all, items at B&H ship free, and I've never quite figured out what dictates this.