Vintage Oyster Speedking authentic?

[Rlx4mle]

Hello,
My mom gave me my grandfather’s Rolex from when he was a merchant marine travelling the world. I would like to know if it’s authentic, how old it is and how much you think the cost would be to make it look/work better? I know it looks like it’s in rough shape, but I would love to restore and wear it for sentimental reasons. It still runs as soon as I wind it a couple of times. I’ve taken a few pictures, hopefully they’re clear enough to see. Thanks in advance for any and all help.

Amy

[offrdmania]

Looks ok to me and before anyone says it, I do not think the dial has been repainted.. Im not sure whats going on with the bracelet clasp as that is not a Rolex coronet logo on it. If you can pop open the clasp and take pictures of what is marked on the clasp blades it will really help. I suspect the bracelet is from another maker even though the 51 end links look correct. The coronet on the clasp may have been modified to represent something in the merchant marines but who knows.
It has had some service work done to it, the crown is a newer service replacement and it looks like the crystal may have been replaced; probably at the same time.
If it fits you then I would wear it and enjoy it. Be sure to thread that crown back on so that dust, debris or water dont get into the watch.

[TimeLord2]

Looks very much like this one on EBAY https://www.ebay.com/itm/284558383297 . Try https://ridleywatchmakers.com/ to ask about service or another CW21 certified watchmaker. Phillip is very well regarded on this forum for vintage Rolex. Lovely watch!