Thanks for the pictures. That looks exactly like my carb.
I do have the flapper valves next to the body but they don't look like they fit tight to the body and they are made of a stiff plastic, not like the original black gasket type. That is the only thing that I can see that is wrong. On the diafram side it seems to me that the diafram would fit next to the body and then the gasket but the picture shows it the other way. I have tried it both ways but no difference. You can see it in the link.
I'm going to order a new carb kit that looks like it has the original type fuel pump gasket and try again. I hate to give up and buy a new carb.