Venus Auto would be my number one pick. Most of the people I know have gotten their japanese motor sets from them. I do suggest you purchace a whole front clip instead of just a motor. It saves on the headache when you start finding that there are little things missing. But I've also found out that their service is either hit or miss, but in the end everyone I've known who had issues had them resolved with no hassle.
For somewere closer to the bay I suggest japan parts in SSF.
As for cheap and good... You'll be looking at around 2k or so. Most of the motors will have 40k miles on them. IMO if you have the luck to pick through some motors, try and find ones that arn't modded. Because chances are they haven't been already beaten to hell.
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