I'm sure the freewheel is from Shimano, as thumpism suggests. Older Shimano wide-rage freewheels used skip-tooth large cogs, to aid shifting. This is not the same as the older skip-tooth single speed and track drivetrains, which used 1" pitch chain. AFAIK, there were no derailleur systems that used 1" pitch chain.

Re: the brakes. "Synchron" brakes were the original dual-pivot calipers, developed first by Gerry Burgess in Britain and licensed to Altenberger and Weinmann, so you may find Synchron calipers from any of these three companies. Interestingly, dual-pivot calipers were only found on low-end bikes until the early 90s, when Shimano started marketing mid and upper level dual pivot calipers. Here's the Gerry Burgess version of the Synchron caliper: