Not sure you can find $50 used analog scope in TO beyond a flea market sale but ~< $200 you can find new low ends scopes.
http://www.a1parts.com/scope/scope.html
Some of the 'scopes in this link seem quite overpriced.
Even the little Analog GBW-ST16B - 10 MHz job at $186..(assuming near-parity for Oz & Canuck Dollars)
Jaycar have a similar one in Oz for $A149,which I would guess to be identical internally,but with some different switches on the front.
I bought one of the Jaycar ones to help me fix my BWD a few years back.
You guessed it! The BWD never got fixed,& the little Chinese unit did a lot of good work,( in spite of it's limited specs) up until I bought a Tek 7613 .
Problems with these little beasts are:
The knobs are crap,& fall off
The BNC connectors are terrible,plus they don't tighten the retaining nuts properly.
My one lost the EHT supply--easy fix,as it is a switchmode ,one transistor had died.
If you had to buy a limited bandwidth 'scope new,I would definitely recommend one of these instead of the really cheap Digitals,which will be quite disappointing.
I still think you should pursue the Hamfest/Flea Market approach,but if you don't have the time,get the little 10MHz Analog,play around with it for a while,till you discover it's limitations (& possibilities),whilst still keeping an eye out for something better.
If you decide to make the jump to a reasonable Digital,have a bit of a browse through this forum,as many people here have been there before.
I don't have a Digital 'scope,& don't really need one,so I can't comment from personal experience,but Rigol 'scopes seem to have a large number of enthusiasts.
VK6ZGO