Bad-Fitting Cab Corner Speaker Enclosures

[damnyankee36]

Does anybody have a recommendation to a set of better fitting speaker enclosures? Here's what I am dealing with at the moment:

They fit well on the sides but they're a few inches too short and don't match the angles of the cab and floor. I could bend the bottom angle section a bit more for a better fit there but that would lower it to the point of having probably a 2" gap at the top.

Are the ones out there all the same? I got the cheapest set on eBay so maybe that's a clue...