First of all, TrueCrypt is open-source, so you could get the source and do whatever you want, provided you know how to program. But the TrueCrypt containers (or partitions, etc) would be incompatible with a non-modified TrueCrypt program.
Moving on, the "iteration count" can't be adjusted without programing. It's not a parameter that you can set anywhere in TrueCrypt. So you can't change it in an upcoming installation of TrueCrypt. And those documents you mention are outdated, 'cause the TrueCrypt docs says:
1000 iterations (or 2000 iterations when HMAC-RIPEMD-160 is used as the underlying hash function) of the key derivation function have to be performed to derive a header key, which increases the time necessary to perform an exhaustive search for passwords (i.e., brute force attack) .
So, it's 1000 to SHA-512 or Whirlpool, and 2000 to RIPEMD-160. It doesn't use SHA-1 anymore.
One more point is that the iteration count might seem to be low, but there's a 512-bit salt with the password. (source: truecrypt pages). That's a very big salt, which prevents rainbow tables (since any pre-computed table would have to begin with 512-bits (64-bytes) passwords).
Of course, salts don't prevent brute-force, since it's not a hidden value. That leaves you with just your password and, perhaps, with a key-file.
--- Edit: the reality about brute-force.
Wikipedia has something about the physical limits on a brute-force attack. If you choose a password that has 128 bits of entropy (that is much more than 16 bytes, since printable characters + numbers + symbols don't use the 256 possible bytes values), problably it won't be breakable before the 4th World War.
XKCD joke is also mandatory about this subject.