Below is a quote from Trigger (Graham) relating to CB550 gaskets but the gist is the same really for the CB750 with the exception of the early K series where only a genuine Honda cylinder head gasket should be used.
Apologies Graham, I don't know how to highlight your original response to the CB550 gaskets so apologies if I misquote you below.
Quote
In my book,
1st is OEM
2nd is Vesrah
3rd is NP ( but be careful as loads listed on ebay but, you will not get a NP)
4th is Athena
5th is NE
all depends on the size of your wallet
And the head being skimmed.
Alternatively, type CB750 gaskets in the search box and you will find a lot of threads on the topic.
Cheers
Dave