Hi ohjohnnybegoode! Welcome to the multiple SC owners' club -
The Brooks still has plenty of miles on it - but I would give it a liberal dose of Proofide top and bottom now and again in a few weeks, then just occasionally thereafter.
Look for cracks on the DR's plastic housing. If there is any you may have to take some advice from this thread for later DR substitutes - There is a plethora to choose from that will work on these bikes.
I would recommend shopping for a Weinmann 750 for the missing brake - the 610 is too short for some of these SC's so unless you get it free - play it safe.