Ok ... The OP does not tell us the age of the sub, what the failure was (for example, my brother had an amp on a PSB sub totally fry during a lightning storm) nor any other actual, useful information.

Let's look outside Axiom at a suitable amp - the Dayton SP-1200 DSP amp could be programmed to work well. It's $600.

We don't know what price the OP considers to be "ridiculous" either.

OP ... several people have asked good questions, with no response.