Several effective ways exist for finding engagement rings at sale prices. As affordable as you wish to search, with some limitations. But chances are, you have not exhausted these potential sources:

• Estate Jewelry and Auctions. These collections inventory one-of -a kind pieces. A vast number of which are no longer available, further enhancing the value you receive. Professional cleaning measures do wonders. Besides, the stone on a fixed mount offers little possibility of wear, assuming it has received reasonably decent care (depending on softness of the setting; gold vs silver, etc).
  
  This can normally be determined on inspection. Sale prices from these buying arenas can approach 40% and greater. While based in larger cities mostly, distance purchases might be made too.
  
  If going this route, check if there is a money back guarantee on purchases (no binding exchange)
  
  
• Start with a main center stone form elsewhere and have it reset. A gorgeous diamond or emerald from your lineage receiveing a new mount might well bring an inexpensive ring. And a new meaning.
  
  If the ring is undersized by not too much, think about having it stretched wider. With the risk involved, a qualified jewelry should do this.
  
  
• Consider a dealer of cut diamonds. Where you buy the stone with a cut shape to your preference at a reduced rate, and thereafter have it mounted.
  
  
• If you cannot afford the ring you currently want, consider buying a modest ring for now with the intent of trading up in the years ahead.
  Not all ring dealers do this, though, and trading up may be based on a percentage-of-value basis. Be aware of your jewelers policy beforehand, and be reasonably assured the standing of the business is stalwart enough to make good on this.