Which Canon lens hood will fit and is preferred for the Canon 55-250 mm lens? I need it to be reversible.
That depends on which lens you have and whether you want the official Canon model or something cheaper. If you have the EF-S 55-250mm f/4-5.6 IS STM, you want an ET-63 lens hood (or compatible replacement). If you have the EF-S 55-250mm f/4-5.6 IS II, then you want an ET-60 hood (or compatible replacement). For other lens models, look up the lens on Canon's web site and click the tab for accessories. From there you can see which lens hood is the lens needs.
Canon hood usually cost around $30, and are very well made -- they fit just right, feel like they're made of high quality plastic, and usually have a nice felt-like flocking on the inside. Cheaper versions usually cost $5-10, don't have the flocking, may or may not fit perfectly, and often don't feel quite as sturdy. But they all block light from the side and reduce flare just fine.
Any lens hood that fits in the forward direction can be mounted in the reverse direction as well -- the bayonet mount works the same either way.