It appears historical intraday datasets for options run several thousand dollars per symbol from most of the exchanges and data providers ie. CME Datamine, CBOE LiveVol, AlgoSeek.
I've gotten a quote from iVolatility which seems to have reasonable pricing for 1min intraday data (~$1000 for 2 symbols) though their timeframe only goes back to Aug 2011. Their data format includes IV & Greeks which is ideal.
If there's any interest in a group buy for the symbols above or if you're able to share advice on more affordable sources, pls post below or feel free to PM me. Thanks.