Records for Roman Catholic Church for Pančevo are available to be researched in Pančevo state historical archive in Serbia. ( you would need to hire a researcher for that, and in a week or so we will have a list of recommended researchers up posted in the research section of our website : http://www.rodoslovlje.com/documentation/research ).

You should start with obtaining the birth record of your ancestor from these original records, and explore any further lineage before or after his birth,  and look for descendants of the same family in these original records.

For Pančevo, the records are available for the period 1718 -1895 for public research.

I do not know if LDS has these records on microfilm, check their catalog at family search . org. - if they have it you could then research the microfilms in a LDS center in your country - and I will help you with interpreting them - older records will be in Latin, and later ones (second half of the XIX century)  will be in Hungarian language.

I am sure that Donauschwaben Villages Helping Hands website and their coordinators for Pančevo will be able to help you with specific information on when family Zeiler first settled in Pančevo, and from where they originated before the colonisation to Banat area.

The website:

http://www.dvhh.org/

Other than that, I will check the available period records over here for any mention of the surname variants you provided and post here if I find anything.

So far locally I see only a couple of people from Serbia with surname Zeiler that are from Banat area and can  be found on facebook or in current public records, as well as a Zeiler who authored one of these village-family books for a village in Croatia - migrations back and forth across this whole region between Donauschwaben communities were quite common in XIX century.