As far as I know, Hypermax were the only guys to ever P-pump an IDI. A guy on oilburners.net called Hypermax and asked about building a replica of that 1200 HP IDI and was quoted about $25,000 - $30,00.
You can get 8 cylinder P-pumps from Sheid and Columbus Diesel
Josh, most of those rigs in the DP article are oilburners guys. Most if not all of the old IDI talent on TDS are on OB now.
Heath