You can replace either (or both) think with believe.
(Of course, "I believe you believe ..." is no better.)
If you feel (another alternative to think)
that "I think you think ..." is cumbersome because it's too long,
I can't really help you.
But, if you object primarily to the repetition,
here's another long-winded variant:
It's my understanding (or, simply, "I understand")
that your position is ...
Another approach is to state the other person's thought (/belief/opinion)
in a more direct way, implying that the person thinks it; e.g.,
I think you support delaying the announcement.
I believe you object to the design of the logo.
Similarly, "approve [of]", "oppose", etc.