you will be able to get a ranger ss3900 one that will fit it, but will show signal,rf power and swr instead of signal rf power and modulation, you may be able to open it up and switch the cards, not sure as never needed to do it, but jackson s meters are very hard to source, your best bet if you want an original is from a scrapper or a new one try Piet at Avera.NL
E-mail
info@avera.nl
His English is superb, no need to translate to Dutch, you won't need part number either, he will know it. He is one of President Europe's main dealers
as old meter was probably aligned before it broke, new meter will probably not be that far off, if it is then as Robb says a sigal generator is best way to put it right and instructions can be found in manual, either at cb tricks or servicedocs.com under president in the search by brand drop down menu
it might not be meter, could be sensing diodes.
Its not just DBFL222 that thinks its a great ssb radio, most Europeans love it, shit on AM as low level modulated but works well on FM and killer on SSB, I ain't had an 11m radio that sounded better on SSB, either rx or tx
if you give us more idea of what it does do instead of just s meter isn't working i could be more specific.
does rf power meter work when tx'ing?
does modulation meter work?
are you still getting receive despite meter not working?
is it just lights not working or actual meter?
if meter moves in any mode, how far?
the more you tell the more easier it is to diagnose the fault.
it might not be the meter at fault,could be faulty meter adjust vr, could be fucked diodes,could be misaligned receiver, could be a whole host of things,
its not always the part that appears faulty causing the fault.