Hi Guy's thanks for your suggestions,
Only the RM125N 1979, a DR125SM and a TS185R Share the same Bolt pattern and 428 size,
50 tooth is my only off the size and luckily JT has this in El cheap steel or expensive Ally.
After i settle on the gearing i really need i will get a quality custom made up.
The phone number for the chain gang just rang through numerous times today
U21b/ 500 Seventeen Mile Rocks Rd, Seventeen Mile Rocks, QLD, 4073
07 33768488
Mark.