It is a condition for JB that the applicant is both available for, and looking for, work. However, at 63 it is likely you will be granted it. But it lasts for 9 months only. After that you could apply for Jobseekers Allowance but you would be refused on the means test. Assuming you are granted JB you will automatically get PRSI credits with it and you should be able to continue to sign for credits afterwards, even though you won't get any JA.
As an alternative you could maintain your PRSI record with voluntary contributions. Bear in mind for State Pension purposes it is your record up to 31st Dec in the year you turn 65 that counts.
You should be eligible for the over-65 payment. But all of this is per current criteria and things may have changed in 8-10 years.