Part of a project on 1.2Ghz that will include this band-pass filter.

Main dimensions got online via the tool here: https://www.changpuak.ch/electronics/interdigital_bandpass_filter_designer.php

Some details of similar construction for different frequency range (ADS-B) here: https://keptenkurk.wordpress.com/2014/11/05/a-homebrew-1090mhz-ads-b-filter/

 

My construction:

 

Used FR4 double sided PCB for the sides and brass for elements, bottom and top

 

Online results example for dimensions:

 And the outcome:

 

Regarding results; not the best optimization for attenuation but not bad either considering the dimensions and construction not to the greatest dimensional andards:

Have a nice day!