I also own a 72 TW. Like you I replaced the furnace. Lately I am replacing lights and plumbing-pump through water heater-(neon, LED & pex).
I would just get any range that fits and that you like unless you are doing a restoration, in which case you may be hunting a bit to find one in good shape. Ther are plenty of them out there.
I have generally found that renovating has worked out better than restoring. Getting back on subject,...try a local RV dealer and see if they have something from a wreck or demo that has a good price. If worse comes to worse...buy new. The nice thing about new is you can get a few more choices. You can also customize and put a burner top & a micro wave in. something that woule require a bit of re-wiring but still it is something not available in the original. I have thought about doing that but it would be down the road a bit. Any, try your local RV dealers, a friend of mine redid an old SOB motor home with salvage applicances. My replacement furnace was just a used NT20s that I modified and built a carriage for. It uses less juice per hour of running (LP & DC).
Good luck finding your range, by the way I have also seen some on ebay every now & then.