Hi team, 

I'm needing to replace a couple of LNBs on my triple lnb dish installation and it seems the ones that fit my mounting plate may no longer be readily available. They have these weird raised notches underneath that fit into the mount plate and no others seem to fit. Before I go the other way and replace the whole mount I thought I'd ask here. The only thing written on them for identification is Gold 1040 and they're 11.3k.
Below is an image of the LNB under-side and the mount plate it has to go in to.

I am looking either to buy two of the right LNB's if someone has a couple sitting around. If not what is the best option to replace these with. The mounting clamp is looking pretty tired too, so it's possible I'll need to replace that too.

Thanks for your help. 
Matt