@Eric *****
You can easily take $10,000 or even $1,000,000 USD or more from USA to Thailand.
It can be a cashiers check, cash, gold or negotiable instruments.
The only requirement is that you must declare values over a certain amount to customs agents at both borders.
In your case $10,000 USD to US and $20,000 USD in Thailand.
You will want a paper trail showing the money was legally imported should you want a visa in some provinces, or to buy a condo because you have to prove the origin.
Many people prefer to transfer via Wise or bank wire because there is less risk of robbery, theft or loss.