You can read about the really good/excellent examples often seen at "Joesalter.com", but gun shows can be your best bet for actual deals.
A decent #4 with matching bolt/action can list for about $200-300 within two hours of Memphis. Mine was at $300, but a guy with a good Savage only wanted $200 at the Batesville, MS show last summer.
The guy with the good Savage could not remember how to remove the bolt and so I kept on walking to find an ATM, to buy the other, though higher-priced. For me, the bore condition is the primary objective: A low price does nothing for me if the bore is dull and worn.
Joesalter's retail prices can be high, but his descriptions of the better rifles can help when checking over good Enfields at gun shows.
My second "Jungle Carbine" listed for only $350 last September at the Memphis show, certainly average condition for the age, pretty accurate. They are very handy carbines with good power.
The first #5 came from "Joesalter", but I did not want to pay any more shipping+FFL costs, there for now only buy at shows.
What a shame that so many Battle Rifles appear to have been sporterized over the decades. I never give these a second glance.