Again, I'd suggest doing some research using google. But for crown, my first guess would be a screwdown crown with Rolex coronet and Swiss cross. There are many similar variants of bubble-back movements, so it's not easy to tell from one photo. An experienced watchmaker could tell, but here is some information I found in a few minutes using google.
According to this page (and I have no idea if it's correct), your movement is an A260:
https://www.timeconnectioninc.com/pa...6234-thru-6500
Here is the eBay listing for your purchase.
https://www.ebay.com/itm/266759438601
Here is another thread on your reference.
https://www.rolexforums.com/showthread.php?t=102518
Keep searching and you will find information.
Also, when creating a thread, it's useful to include some details to help the right people find it. In this case, keywords like ref 6334, bubble-back, etc. would have helped.