Using that invaluable site:
http://www.measuringworth.com/ukcompare/ we can see that £99 in 1936 (cost fo the set when new) is equivalent to about £5K using RPI and £19K using average earnings. This also shows how average earnings have increased compared to the RPI.
I don't think you can get a custom CRT made. A rebuild of a pre-war CRT is about £700 from RACS.