She probably m. before 1837, hence no sign of marriage on FreeBMD.  But not if the 1841 census is to be believed, where she was still Powys and living with her mother.

Nor is there any marriage for an Elizabeth Powys between 1840 and 1860 except for one in Staffs where the bride’s father was Charles Powys and thus not her marriage.

There are 11 Elizabeth Jameses who d. in England on FreeBMD in Jul-Sep 1860 and I cannot say if any were her.  Or she may well have died in USA.

Sounds like a CDM should be awarded to anyone who can find any information on her marriage and death.

July 2016, TFPL: Cracked it, she married using the forename of Letitia and it was in England in 1855 when she would have been 45.

But still no sign of any record of her death.
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July 2016, TFPL: Got hold of the data from the Fawley baptism register:

“15 Nov 1810 Elizabeth Letitia Tertia born 2 May daughter of Thomas & Elizabeth POWYS”

This corrects the spelling of her second forename from Loelitia to Letitia.
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Their marriage from FamilySearch:

First name(s) George
Last name James
Name note -
Marriage year 1855
Marriage date 02 Jan 1855
Marriage place Linchlade
Father's first name(s) George
Father's last name James
Spouse's first name(s) Letitia
Spouse's last name Powys
Spouse's father's first name(s) Thomas
Spouse's father's last name Powys
Residence Linchlade, Buckingham, England
County Buckinghamshire
Country England
Record set England Marriages 1538-1973

Their marriage registration index:

First name(s) GEORGE
Last name JAMES
Marriage quarter 1
Marriage year 1855
Registration month -
MarriageFinder™ GEORGE JAMES married
LETITIA POWYS
District LEIGHTON BUZZARD
District number -
County Bedfordshire
Country England
Volume 3B
Page 495
Record set England & Wales marriages 1837-2008
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