Help with valuation of 78rpm set of records

[EmmaBushell]

i have a dilemma, i have a set of five 78rpm records published in 1949 with original voice recordings and sound effect recordings from 1934-1949 including Hitler, Mussolini, H G Wells, King George VI, Churchill and lots of others they are all in a playable condition and the cover isnt too badly damaged, i want to get it valued but have no idea where to go or who to ask.
any suggestions?

Here is a picture of it:
https://www.facebook.com/photo.php?...=o.19257204144&type=1&relevant_count=1&ref=nf

 

[Mocheman]

Here is the vinyl version of that recording for sale. You can see the different prices people are asking. I don't know if that's helpful or not.
http://www.discogs.com/sell/list?release_id=1985369&ev=rb

I also found an auction site that is selling the one you have and you can see what they value it at.
http://www.mullocksauctions.co.uk/lot-23515-bbc_original_sounds_of_the_time_1934-1949_historic.html