That rifle at Reliable is listed as a Long Branch Mk I (No Star) which makes it one of the rarer standard issue No. 4's out there. In no way representative of No. 4 prices. You should still be able to find good (non-desporterized) No. 4's for $800 or $900 or, occasionally, less. SMLE prices are highly variable depending upon year of manufacture and level of originality. A very good pre-WW1 Mk III could easily go well over $1500 while a somewhat worn late WW1 Mk III* might not get $650. Good looking ones are not always the most valuable, however, as many were refurbished post even WW2.
milsurpo