The reason you are unable to find the record at FamilySearch is that the 1848 Conscriptio for Saros was not filmed by the Mormon Church. JewishGen’s Hungarian Research Division acquired these records from the Slovak State Archive branch in Presov. Here is the announcement that Eric posted to the Hungarian discussion list at the time the records were uploaded to the database:
Thanks to the diligent efforts of our dedicated transcription team, I'm happy to announce completion of the 1848 Jewish census for Saros county, Hungary after 7 months of work. This census will be extremely valuable to genealogists with ancestors and relatives from Saros county.
A total of 9,631 names were transcribed, which include ALL household members (heads of household, their wives and children, and others Other information includes town of residence, age, birthplace, occupation, and relationship to head of household. A total of 343 towns of residence were included.
An older, general description of the 1848 census may be found at https://www.jewishgen.org/databases/Hungary/Census1848.htm Some variation in the general transcription rules were made during transcription of the Saros census, particularly with regard to suffixes which occasionally appeared with town names and surnames.
To help us recover the cost of acquiring this census from the Slovak archive in Presov, contributors of $100 or more to the Slovak Archives Records Project found on the JewishGen, Special JewishGen Projects donations page will be immediately entitled to receive a copy of the completed Excel spreadsheet with all the data. This data will NOT be available to the general public for at least one year, when it will be added to the All-Hungary Database on JewishGen.
If you would like to make a contribution, please go to: https://www.jewishgen.org/JewishGen-erosity/v_projectslist.asp?project_cat=15 and enter your contribution in the box for Slovak Archives Records Project. Forward to me a copy of your electronic receipt and I’ll send the spreadsheet.
If you have any questions, feel free to contact me off-list.
Eric M. Bloch, Coordinator
Vivian Kahn, JewishGen Hungarian Research Director