Based on the information known about Richard Russell there appears to be only one suitable baptism which was to John and Amy Russell in Fakenham in 1778.
Although records may not be complete a FREEREG search in Norfolk found only one marriage for John Russell and Amy.
The death of John Russell in Fakenham in 1778 is assumed to be this man.

If John died in 1778 then according to the register he was 38 years old and so born in 1740.
Various baptisms have been found from this general era, three are possible if the age is correct.

26 Sep 1742		Helhoughton	to John and Mary
24 Nov 1740		Norfolk	Feltwell to Simon and Mary
16 Jan 1740/41	Hempstead by Holt to George (mothers not listed in this register)
Copies of all these registers have been downloaded.

Of these Helhoughton is nearest and then Hempstead.
The age of John from Helhoughton is 2 years out.
On the basis of the evidence available the baptism at Hempstead is slightly more likely but is inadequate to be sure.