The most common and most likely answer to this crossword clue is the 6 letter word WAMPUM
W
A
M
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M
Buddy explains!

The straight part
We know that "Old N American Indian ready" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case old n american indian ready = wampum.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does WAMPUM mean?
WAMPUM noun- Small beads made from polished shells, especially white ones, formerly used as money and jewelry by certain Native American peoples.
- A string of such beads.
- Money.