Yes!  You can convert a short tug pair harness to one or two single horse harnesses.  This BioThane synthetic package includes those pieces for one single harness.  Of course, you can order each part separately, especially if you want different reins.  Stainless steel hardware.

Includes:

• Single Reins - plain, with buckle on end and pinky loop
• Breeching Straps - for in place of the side backers
  
• Shaft Tugs - for in place of the trace bearers;  Open tugs for straight shafts or Quick Release tugs for closed end shafts
  

Measurements of the tug bearing straps on the saddle and the overgirth buckles are needed for any harnesses that are not IVC brand.