In some circumstances it can help to find components by looking at the schematic and tracing back from the valve socket pin number(s)
Here's a link to the most popular site for valve pin connections and valve data:
http://www.r-type.org/inx/main-inx.htm
In the first box is the 1st number or letter of the valves you might be interested in, click on then scroll down for a picture and full name/number of the valve then click on that for the pin connections/data etc.
If not found there then try this site, also excellent:
http://www.shinjo.info/frank/index.html
Click on the first character printed on the valve then look for the valve by scrolling down and clicking on it's link.
Lawrence.