Thanks Alan.
I think the original design of the "sliding junior" was for a small radio too. My uninitiated thoughts were:
The capacitor C1 was included to filter rf.
It would definitely need DC blocking capacitor at the input, of say 1uf ?
I would put a resistance between the collector of tr1 and base of tr2, and another from the collector of tr2 to +3v for turn off and protection? Maybe 100ohm and 2ohm respectively?
The circuit seems to me to be a bit upside down

The interconnection of the transistors makes them work as one high gain PNP, correct?
Sir Douglas Hall was apparently a respected electronic author, and a member of another forum said he built the sliding junior as a kid, he said it was temperamental to get working and the audio quality wasn't great on quiet to loud step level transitions, but it did work.
It may be worth breadboarding. If it works it would be interesting to find out
HOW. If it doesn't work its still something to put in the project notes
At my school the nurds are as cool as the athletes, I always enjoyed helping Dad with his hobby stuff, he worked as an industrial control and instrumentation design engineer and made stuff like this look easy, so I thought it was easy! But its fun finding out that its not.
Can't wait to carry on later this week analysing your circuit too.
Laters.
Luv, Ami.