The 1000 8m ones mine uses an Optibelt Omega HP 1000 8m, (20mm wide) I did a couple of thousand miles no issues but hasnt been used in 9 years, I' spoke with Optibelt and bought direct £25 posted per.
Optibelt Warrington 01925 415777 iirc
Mine toothies are the Austrian ones people were buying a few years back.