Glad to see you on board, however sad to here about your problems. First off about your trap problems if I understand your problem the line that connects the wire trap to the shock cord should be replaced on ALL your traps with a 2'-6" 5/16" dia. spec. line. Also check on how you are tieing off your ends. If however your saying that your wires have failed then replace them ALL.
As for you jib block, if your jaws have locked up you can replace the springs on those puppies remember stainless steel. If the rachet has locked up well try sum marine lub and pray. Sounds like some dirt has spent to much time in your system, time to do some house cleaning. If that fails then start your search, this is not a hard item to get.
Good luck
Harvey