sounds like you got a good deal, congrats. These Puch/A-D frames with some or all 531 tubing were an under-the-radar bargain and were perfect candidates for upgrading the components. Even with those 1319 Rigida 27" wheels (rep for being a soft alloy plus skinny which led to short lifespan) I'd use them until the tires are shot or a wheel gets ruined, then upgrade to a stronger 700C rim (something like a double-wall Sun CR-18) and the longer-reach brakes you MIGHT then require.
Happy building!