93150 bracelet diver extension

[Mscott842]

I have a 93150 bracelet dated 1984. It came with an Explorer II (16550). The bracelet is too short and I need to extend with two links. Questions:

1) Does this clasp have an extension sunstitute link from GMT?
2) In first photo you can see that I added a link but it looks very different because it's brushed not steel. What link do I need to match the rest of them?
3) Can I convert this back to an original diver extension clasp? What do I need to do it - link with small circle inscribed in it for pressing extension back into clasp? anything else?

Sorry if questiins are convoluted but I spent quite some time researching online and it only made me more confused. Thanks in advance for any input.