Caught in the old bind of owning an overtaxed dust collection system but lacking the funds to replace the system? Instead of replacing it, try improving the performance of system components. Tweaking one thing or nudging another can often improve the entire system.
Most dust collectors, and particularly pulse-jet systems (the most commonly used type), don't just "wear out." They might corrode and require replacement, but pulse-jet collectors have few moving parts to wear. A well-maintained dust collector and fan that is not subject to corrosion or erosion can perform just as well when it is 10 or 20 years old as it did when it was first installed. The problem might be that maintenance has not been adequately carried out, resulting in an underperforming system, or that the requirements of the system have changed.