Just register with a contract agency - PARC is probable the least worst - and see what comes out. A mate registered with PARC at age 58 and is now working in China, despite the advertised age limit of 55.
But beware that Chinese, Japanese and Korean medicals are tougher than NASA's. Any issues with the ticker, or what they consider to be a high BMI will exclude you. My 58 year old mate is so thin, he makes most bicycles look overweight.