For an 86 TRX250R or 85-86 ATC250R, I don't know anyone makes new ones except BDT. If you can't find them, or no one else can assist, or you can't find used ones, BDT Motorsports has New ones made from Titanium. Currently the mounts are at Electropolish. We are releasing these in early December as another 'Trick' BDT custom part for the 250R.
The BDT Titanium front ATC250R & TRX250R engine mounts are 60% stronger than OEM, and are lighter by approximately -40% vs OEM....very 'Trick' part.