Turntable

While I do not believe personally you really need  a mat with the acrylic platter the 5mm Achromat is a great choice, had one and used it for years and yes I ordered from a dealer in England too.
Just remember though you are now adding 5mm to the height your record is sitting at relative to the stylus so you will need to adjust vta to suit

My old Rega Planar 2 with upgraded acrylic platter sounds best to my ears with record direct on the platter, no mat at all but....ymmv.

Enjoy!