This is what I use, the pin wrenches for the spring tensioner, flat wrench for the eccentric tensioners, flywheel lock, and Porsche tool P9201 tension gauge.
I think you can get away without the flat wrench. A vintage Hazet or Gedore regular wrench (think like the ones in your factory tool kit) are slightly thinner than modern wrenches at the open end, one of those may work. If not you can always grind down a Princess Auto cheapie wrench.