If you're up for a DIY effort and can live with lower power, you can build a Neurochrome Mod-86 for under $400. Other than that, the hypex modules are your best bet. If you can scavenge a case, you can do a NC400 build for under $1000. Current pricing (minus shipping) for 2 amp modules and a single PS is about $750 I think. The older UCD modules are even cheaper, and many report that they are still very close to the NC400 in performance.