Crespera lugs and wrap over seat stays plus hanger for centre pull rear brake almost certainly means its made of Tru-Wel tubing. Firms are a different matter though :)
They are RYS5 cranks, AFAIK they only made one version of that crank set and thats it.
If they are true pista then they are rare, bitd we ground the inside flange off the LA5 road cranks :)
That's a very good condition dynatech, they have a habit if corroding where the rear seat stats attach, that example looks perfect. And the colour's original too :)
Damn, that Emperor is just a tad too small, Pongo is turning in his grave .....
Shaun