Platter wobble


I have a Technics SL-BD20D and the platter has a noticeable wobble while spinning. ive tried a couple mats - cork and acrylic - which made the wobble much more apparent.  The rigid acrylic platter would not lay flat on the platter. 

Anything I can do? Is there a way to test what the issue is?  Is there an quality aftermarket platter that I can use?

Thanks!
leemaze
Fingers crossed. If it is, put it on a stable table on a sheet of granite and treat yourself to an Audio Technica AT95E cartridge.
Thanks @noromance though it seems the AT95E will not work with my p-mount tonearm. Is there an equivalent p-mount?
Update: Sadly the new one wobbles worst than the original. 

Oh oh well was worth the shot.