I guess OVH is as cheap as it can get. What should be the location of the server? Europe? If so, you can check out solarcom.ch or dragonara.net, although I don't have personal experience with their protection.
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there are some good companies offer ddos protected servers but there is not cheap. But you can contact them to receive discount. maybe they have some discount. try Blacklotus.net or Staminus.net or hyperfilter.com