Baptism & Marriag - Downe & Halstead Parishes - PLEASE

[LUV]

Would someone please do some lookups for me???   

I am not sure how the index is itself 'indexed?' but I assume  it is by Place and then alphabetically by last name? 

I am interested in two families in the areas - Percival and Fuller

Specifically the baptisms/births of any children of -

Richard & Sarah Fuller - would have been 1800-1830 range

John & Elizabeth Percival (nee fuller) - would have been 1830-1850 range

Also I am looking for the marriage of RIchard & Sarah Fuller in Downe around 1800.

John Percival & ELizabeth Fuller married in Halstead in 1829 so some of their first children might have been baptised in that church versus Downe?

Any help of course is always appreciated 

Thanks
LUV