Best Source for SPxx Day-session Tick data back 6 years?

[Kenlow7@xxxxxxx]

Hi list -

I need day session SPxx tick data for the period 1/1/94
through 4/1/98.   It's been a while since I shopped around
for data history - anyone know who's got the most reliable
data for the lowest price these days?   Thanks in advance,

Ken Low