Speaking from experience (just did both those scenarios two weeks ago) either option is fine. The problem youll run into by just finding a cheap wooden box, is it will either cost you as much as one of the better custom boxes, or it will feel really light. You could consider something like this, but the prebuilt box i found was at ross for like $10.
Alternately, if youre looking to build one yourself, just search youtube for videos on building boxes and you can use anything from there. I just got a 24x24 MDF board that i cut the parts from. Itll take a bit longer, but cost about the same to make a case that feels much better. Check my posts for the pic i put up of my case.