A good primary source for a roman amour would be the leftovers of the actual amour. Multiple museums and private collectors worldwide have original pieces. They vary a lot in regards to age and state of preservation. Other primary sources the give you details about Roman amour and weopens could for example be texts, mosaics and frescos.

If you wanted to get example sources you will have to be more specific when it comes to the time period and than I am sure someone more qualified in that time period will be able to help you find what you are looking for.