6500 at that match, but I'm guessing you couldn't tell how many Albion went up due to lack of segregation (and goals!)
http://thegoldstonewrap.com/2013/11/29/1973-brighton-0-4-walton-hersham-albions-worst-fa-cup-defeat/
That's a hidden gem! Was it a spelling test you missed, by any chance?:)
'...amateurs Walton and Hersham...' They were, of course, 'shamateurs', as I believe were every club in the Isthmian League (I think it still had only the one division at this point, although it absorbed the three divisions of the Athenian League one at a time). The FA Amateur Cup competition...
This is an amazing coincidence as I bought one of those this very evening from Home Bargains (£5.99), so I presumed it was what this thread concerned. I have little idea of what the OP is talking about!