The Shimano M520 pedals are the cheapest in the Shimano range but it is possible to buy cheaper in other makes.
But I got my first set of M520's at least 10 years ago (They were M515's then) Still have them and they have never been serviced. They are pretty reliable.
Shoes and there are cheaper than shimano but try before you buy.
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How long was I in the army? Five foot seven.
Spike Milligan