looking at the Esoteric T1 website, (scroll all the way to the bottom) they have an arm board for the Reed 5T/5A. looking at the Reed website it appears that the 5P uses the same arm board mount. you would have to investigate to make sure, of course. but odds are you are good to go.
you would have your dealer check with Reed and Esoteric both that the geometry and weight of 5P arm would work properly. they have their process very dialed in since each arm board is custom. the downside is that it does take time. but the quality is first rate.
I use the TEAC washi paper mat, as well as the Dohmann record clamp on my T1. I find it has dramatically lowered the background noise in my playback, but possibly at a small expense of reduced liveliness.
Those are both really great products though, and we are talking about personal taste here.