Power Conditioner For Client Sites With Dirty Power?

Been noticing an issue with our surveillance equipment lately as we've started to expand into the southern US market. It seems as if surges, brownouts, voltage sag, etc. are common in these regions and the power isn't as clean as we're used to seeing in the mid-Atlantic. This has resulted in lost equipment (hard drives, power supplies, switches, etc.) that we're just not used to seeing anywhere else.

We've had great luck with placing APC Voltage Regulators behind our UPS units back at the headend where the majority of our equipment resides at these effected sites, but that still leaves our most vulnerable assets (pole mounted equipment) with no protection. After loosing more than a few Ubiquti radios, PoE switches, etc. to lightning strikes, we started installing Ditek surge protection behind our NEMA boxes, but that still doesn't address the dirty power issue at the pole.

My question is: is there a NEMA/pole friendly (DIN rail mountable, etc.) voltage regulator out there that doesn't cost an arm and a leg? I've seen the SolaHD devices, but in order to match the specs of the ~$50 APC desktop unit linked above, you're looking at a ~$1000 product with that particular brand.

Any help would be greatly appreciated!